Initial commit

vs4win/Chapter10/Ch10Ex02DataSerialization/Category.cs

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+using System.ComponentModel.DataAnnotations.Schema; // [Column]
+
+namespace Packt.Shared;
+
+public class Category
+{
+  // these properties map to columns in the database
+  public int CategoryId { get; set; }
+
+  public string? CategoryName { get; set; }
+
+  [Column(TypeName = "ntext")]
+  public string? Description { get; set; }
+
+  // defines a navigation property for related rows
+  public virtual ICollection<Product> Products { get; set; }
+
+  public Category()
+  {
+    // to enable developers to add products to a Category we must
+    // initialize the navigation property to an empty collection
+    Products = new HashSet<Product>();
+  }
+}

vs4win/Chapter10/Ch10Ex02DataSerialization/Ch10Ex02DataSerialization.csproj

@@ -0,0 +1,24 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net7.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+	<ItemGroup>
+		<Using Include="System.Console" Static="true" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="7.0.0-*" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<None Update="Northwind.db">
+			<CopyToOutputDirectory>Always</CopyToOutputDirectory>
+		</None>
+	</ItemGroup>
+
+</Project>

vs4win/Chapter10/Ch10Ex02DataSerialization/Northwind.cs

@@ -0,0 +1,47 @@
+using Microsoft.EntityFrameworkCore; // DbContext, DbContextOptionsBuilder
+using Microsoft.EntityFrameworkCore.Diagnostics;
+
+namespace Packt.Shared;
+
+// this manages the connection to the database
+public class Northwind : DbContext
+{
+  // these properties map to tables in the database
+  public DbSet<Category>? Categories { get; set; }
+  public DbSet<Product>? Products { get; set; }
+
+  protected override void OnConfiguring(
+    DbContextOptionsBuilder optionsBuilder)
+  {
+    string path = Path.Combine(
+      Environment.CurrentDirectory, "Northwind.db");
+
+    string connection = $"Filename={path}";
+
+    ConsoleColor previousColor = ForegroundColor;
+    ForegroundColor = ConsoleColor.DarkYellow;
+    WriteLine($"Connection: {connection}");
+    ForegroundColor = previousColor;
+
+    optionsBuilder.UseSqlite(connection);
+  }
+
+  protected override void OnModelCreating(
+    ModelBuilder modelBuilder)
+  {
+    // example of using Fluent API instead of attributes
+    // to limit the length of a category name to 15
+    modelBuilder.Entity<Category>()
+      .Property(category => category.CategoryName)
+      .IsRequired() // NOT NULL
+      .HasMaxLength(15);
+
+    if (Database.ProviderName?.Contains("Sqlite") ?? false)
+    {
+      // added to "fix" the lack of decimal support in SQLite
+      modelBuilder.Entity<Product>()
+        .Property(product => product.Cost)
+        .HasConversion<double>();
+    }
+  }
+}

vs4win/Chapter10/Ch10Ex02DataSerialization/Product.cs

@@ -0,0 +1,26 @@
+using System.ComponentModel.DataAnnotations; // [Required], [StringLength]
+using System.ComponentModel.DataAnnotations.Schema; // [Column]
+
+namespace Packt.Shared;
+
+public class Product
+{
+  public int ProductId { get; set; } // primary key
+
+  [Required]
+  [StringLength(40)]
+  public string ProductName { get; set; } = null!;
+
+  [Column("UnitPrice", TypeName = "money")]
+  public decimal? Cost { get; set; } // property name != column name
+
+  [Column("UnitsInStock")]
+  public short? Stock { get; set; }
+
+  public bool Discontinued { get; set; }
+
+  // these two define the foreign key relationship
+  // to the Categories table
+  public int CategoryId { get; set; }
+  public virtual Category Category { get; set; } = null!;
+}

vs4win/Chapter10/Ch10Ex02DataSerialization/Program.Functions.cs

@@ -0,0 +1,163 @@
+using System.Xml; // XmlWriter
+using System.Text.Json; // Utf8JsonWriter, JsonWriterOptions
+using Packt.Shared; // Category, Product
+
+using static System.IO.Path;
+using static System.Environment;
+
+// we want to easily show the difference between outputting
+// XML using elements or attributes so we will define a 
+// delegate to reference the two different methods.
+
+delegate void WriteDataDelegate(string name, string? value);
+
+partial class Program
+{
+  static void GenerateXmlFile(
+    IQueryable<Category> categories, bool useAttributes = true)
+  {
+    string which = useAttributes ? "attibutes" : "elements";
+
+    string xmlFile = $"categories-and-products-using-{which}.xml";
+
+    using (FileStream xmlStream = File.Create(
+      Combine(CurrentDirectory, xmlFile)))
+    {
+      using (XmlWriter xml = XmlWriter.Create(xmlStream,
+        new XmlWriterSettings { Indent = true }))
+      {
+
+        WriteDataDelegate writeMethod;
+
+        if (useAttributes)
+        {
+          writeMethod = xml.WriteAttributeString;
+        }
+        else // use elements
+        {
+          writeMethod = xml.WriteElementString;
+        }
+
+        xml.WriteStartDocument();
+        xml.WriteStartElement("categories");
+
+        foreach (Category c in categories)
+        {
+          xml.WriteStartElement("category");
+          writeMethod("id", c.CategoryId.ToString());
+          writeMethod("name", c.CategoryName);
+          writeMethod("desc", c.Description);
+          writeMethod("product_count", c.Products.Count.ToString());
+          xml.WriteStartElement("products");
+
+          foreach (Product p in c.Products)
+          {
+            xml.WriteStartElement("product");
+
+            writeMethod("id", p.ProductId.ToString());
+            writeMethod("name", p.ProductName);
+            writeMethod("cost", p.Cost is null ? "0" : p.Cost.Value.ToString());
+            writeMethod("stock", p.Stock.ToString());
+            writeMethod("discontinued", p.Discontinued.ToString());
+
+            xml.WriteEndElement(); // </product>
+          }
+          xml.WriteEndElement(); // </products>
+          xml.WriteEndElement(); // </category>
+        }
+        xml.WriteEndElement(); // </categories>
+      }
+    }
+
+    WriteLine("{0} contains {1:N0} bytes.",
+      arg0: xmlFile,
+      arg1: new FileInfo(xmlFile).Length);
+  }
+
+  static void GenerateCsvFile(IQueryable<Category> categories)
+  {
+    string csvFile = "categories-and-products.csv";
+
+    using (FileStream csvStream = File.Create(Combine(CurrentDirectory, csvFile)))
+    {
+      using (StreamWriter csv = new(csvStream))
+      {
+
+        csv.WriteLine("CategoryId,CategoryName,Description,ProductId,ProductName,Cost,Stock,Discontinued");
+
+        foreach (Category c in categories)
+        {
+          foreach (Product p in c.Products)
+          {
+            csv.Write("{0},\"{1}\",\"{2}\",",
+              arg0: c.CategoryId,
+              arg1: c.CategoryName,
+              arg2: c.Description);
+
+            csv.Write("{0},\"{1}\",{2},",
+              arg0: p.ProductId,
+              arg1: p.ProductName,
+              arg2: p.Cost is null ? 0 : p.Cost.Value);
+
+            csv.WriteLine("{0},{1}",
+              arg0: p.Stock,
+              arg1: p.Discontinued);
+          }
+        }
+      }
+    }
+
+    WriteLine("{0} contains {1:N0} bytes.",
+      arg0: csvFile,
+      arg1: new FileInfo(csvFile).Length);
+  }
+
+  static void GenerateJsonFile(IQueryable<Category> categories)
+  {
+    string jsonFile = "categories-and-products.json";
+
+    using (FileStream jsonStream = File.Create(Combine(CurrentDirectory, jsonFile)))
+    {
+      using (Utf8JsonWriter json = new(jsonStream,
+        new JsonWriterOptions { Indented = true }))
+      {
+        json.WriteStartObject();
+        json.WriteStartArray("categories");
+
+        foreach (Category c in categories)
+        {
+          json.WriteStartObject();
+
+          json.WriteNumber("id", c.CategoryId);
+          json.WriteString("name", c.CategoryName);
+          json.WriteString("desc", c.Description);
+          json.WriteNumber("product_count", c.Products.Count);
+
+          json.WriteStartArray("products");
+
+          foreach (Product p in c.Products)
+          {
+            json.WriteStartObject();
+
+            json.WriteNumber("id", p.ProductId);
+            json.WriteString("name", p.ProductName);
+            json.WriteNumber("cost", p.Cost is null ? 0 : p.Cost.Value);
+            json.WriteNumber("stock", p.Stock is null ? 0 : p.Stock.Value);
+            json.WriteBoolean("discontinued", p.Discontinued);
+
+            json.WriteEndObject(); // product
+          }
+          json.WriteEndArray(); // products
+          json.WriteEndObject(); // category
+        }
+        json.WriteEndArray(); // categories
+        json.WriteEndObject();
+      }
+    }
+
+    WriteLine("{0} contains {1:N0} bytes.",
+      arg0: jsonFile,
+      arg1: new FileInfo(jsonFile).Length);
+  }
+}
+

vs4win/Chapter10/Ch10Ex02DataSerialization/Program.cs

@@ -0,0 +1,23 @@
+using Microsoft.EntityFrameworkCore; // Include extension method
+using Packt.Shared; // Northwind, Category, Product
+
+WriteLine("Creating four files containing serialized categories and products.");
+
+using (Northwind db = new())
+{
+  // a query to get all categories and their related products 
+  IQueryable<Category>? categories = db.Categories?.Include(c => c.Products);
+
+  if (categories is null)
+  {
+    WriteLine("No categories found.");
+    return;
+  }
+
+  GenerateXmlFile(categories);
+  GenerateXmlFile(categories, useAttributes: false);
+  GenerateCsvFile(categories);
+  GenerateJsonFile(categories);
+
+  WriteLine($"Current directory: {Environment.CurrentDirectory}");
+}

vs4win/Chapter10/Chapter10.sln

@@ -0,0 +1,37 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.2.32210.308
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkingWithEFCore", "WorkingWithEFCore\WorkingWithEFCore.csproj", "{4D815158-DA92-4AD6-A417-BEC800167D1E}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "CoursesAndStudents", "CoursesAndStudents\CoursesAndStudents.csproj", "{B4E2819E-6E1B-4314-BBC4-80253EC7764E}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Ch10Ex02DataSerialization", "Ch10Ex02DataSerialization\Ch10Ex02DataSerialization.csproj", "{C9B3475A-66BB-48DC-B0A7-643A415A3D51}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{4D815158-DA92-4AD6-A417-BEC800167D1E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{4D815158-DA92-4AD6-A417-BEC800167D1E}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{4D815158-DA92-4AD6-A417-BEC800167D1E}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{4D815158-DA92-4AD6-A417-BEC800167D1E}.Release|Any CPU.Build.0 = Release|Any CPU
+		{B4E2819E-6E1B-4314-BBC4-80253EC7764E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{B4E2819E-6E1B-4314-BBC4-80253EC7764E}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{B4E2819E-6E1B-4314-BBC4-80253EC7764E}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{B4E2819E-6E1B-4314-BBC4-80253EC7764E}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C9B3475A-66BB-48DC-B0A7-643A415A3D51}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C9B3475A-66BB-48DC-B0A7-643A415A3D51}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C9B3475A-66BB-48DC-B0A7-643A415A3D51}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C9B3475A-66BB-48DC-B0A7-643A415A3D51}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {FFE356D0-B615-4575-B486-42CBA73ED30C}
+	EndGlobalSection
+EndGlobal

vs4win/Chapter10/CoursesAndStudents/Academy.cs

@@ -0,0 +1,91 @@
+using Microsoft.EntityFrameworkCore; // DbContext, DbSet<T>
+
+namespace Packt.Shared;
+
+public class Academy : DbContext
+{
+  public DbSet<Student>? Students { get; set; }
+  public DbSet<Course>? Courses { get; set; }
+
+  protected override void OnConfiguring(
+    DbContextOptionsBuilder optionsBuilder)
+  {
+    string path = Path.Combine(
+      Environment.CurrentDirectory, "Academy.db");
+
+    string connection = $"Filename={path}";
+    // string connection = @"Data Source=.;Initial Catalog=Academy;Integrated Security=true;MultipleActiveResultSets=true;";
+
+    WriteLine($"Connection: {connection}");
+
+    optionsBuilder.UseSqlite(connection);
+    // optionsBuilder.UseSqlServer(connection);
+  }
+
+  protected override void OnModelCreating(ModelBuilder modelBuilder)
+  {
+    // Fluent API validation rules
+    modelBuilder.Entity<Student>()
+      .Property(s => s.LastName).HasMaxLength(30).IsRequired();
+
+    // populate database with sample data
+    Student alice = new()
+    {
+      StudentId = 1,
+      FirstName = "Alice",
+      LastName = "Jones"
+    };
+
+    Student bob = new()
+    {
+      StudentId = 2,
+      FirstName = "Bob",
+      LastName = "Smith"
+    };
+
+    Student cecilia = new()
+    {
+      StudentId = 3,
+      FirstName = "Cecilia",
+      LastName = "Ramirez"
+    };
+
+    Course csharp = new()
+    {
+      CourseId = 1,
+      Title = "C# 10 and .NET 6"
+    };
+
+    Course webdev = new()
+    {
+      CourseId = 2,
+      Title = "Web Development"
+    };
+    
+    Course python = new()
+    {
+      CourseId = 3,
+      Title = "Python for Beginners"
+    };
+
+    modelBuilder.Entity<Student>()
+      .HasData(alice, bob, cecilia);
+
+    modelBuilder.Entity<Course>()
+      .HasData(csharp, webdev, python);
+    
+    modelBuilder.Entity<Course>()
+      .HasMany(c => c.Students)
+      .WithMany(s => s.Courses)
+      .UsingEntity(e => e.HasData(
+        // all students signed up for C# course
+        new { CoursesCourseId = 1, StudentsStudentId = 1 },
+        new { CoursesCourseId = 1, StudentsStudentId = 2 },
+        new { CoursesCourseId = 1, StudentsStudentId = 3 },
+        // only Bob signed up for Web Dev
+        new { CoursesCourseId = 2, StudentsStudentId = 2 },
+        // only Cecilia signed up for Python
+        new { CoursesCourseId = 3, StudentsStudentId = 3 }
+      ));
+  }
+}

vs4win/Chapter10/CoursesAndStudents/Course.cs

@@ -0,0 +1,14 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace Packt.Shared;
+
+public class Course
+{
+  public int CourseId { get; set; }
+
+  [Required]
+  [StringLength(60)]
+  public string? Title { get; set; }
+
+  public ICollection<Student>? Students { get; set; }
+}

vs4win/Chapter10/CoursesAndStudents/CoursesAndStudents.csproj

@@ -0,0 +1,19 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net7.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+	<ItemGroup>
+		<Using Include="System.Console" Static="true" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="7.0.0-*" />
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="7.0.0-*" />
+	</ItemGroup>
+
+</Project>

vs4win/Chapter10/CoursesAndStudents/Program.cs

@@ -0,0 +1,25 @@
+using Microsoft.EntityFrameworkCore; // for GenerateCreateScript()
+using Packt.Shared; // Academy
+
+using (Academy a = new())
+{
+  bool deleted = await a.Database.EnsureDeletedAsync();
+  WriteLine($"Database deleted: {deleted}");
+
+  bool created = await a.Database.EnsureCreatedAsync();
+  WriteLine($"Database created: {created}");
+
+  WriteLine("SQL script used to create database:");
+  WriteLine(a.Database.GenerateCreateScript());
+
+  foreach (Student s in a.Students.Include(s => s.Courses))
+  {
+    WriteLine("{0} {1} attends the following {2} courses:",
+      s.FirstName, s.LastName, s.Courses.Count);
+
+    foreach (Course c in s.Courses)
+    {
+      WriteLine($"  {c.Title}");
+    }
+  }
+}

vs4win/Chapter10/CoursesAndStudents/Student.cs

@@ -0,0 +1,9 @@
+namespace Packt.Shared;
+
+public class Student
+{
+  public int StudentId { get; set; }
+  public string? FirstName { get; set; }
+  public string? LastName { get; set; }
+  public ICollection<Course>? Courses { get; set; }
+}

vs4win/Chapter10/WorkingWithEFCore/AutoGenModels/Category.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
+using System.ComponentModel.DataAnnotations.Schema;
+using Microsoft.EntityFrameworkCore;
+
+namespace WorkingWithEFCore.AutoGen
+{
+    [Index("CategoryName", Name = "CategoryName")]
+    public partial class Category
+    {
+        public Category()
+        {
+            Products = new HashSet<Product>();
+        }
+
+        [Key]
+        public long CategoryId { get; set; }
+        [Column(TypeName = "nvarchar (15)")]
+        public string CategoryName { get; set; } = null!;
+        [Column(TypeName = "ntext")]
+        public string? Description { get; set; }
+        [Column(TypeName = "image")]
+        public byte[]? Picture { get; set; }
+
+        [InverseProperty("Category")]
+        public virtual ICollection<Product> Products { get; set; }
+    }
+}

vs4win/Chapter10/WorkingWithEFCore/AutoGenModels/Northwind.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata;
+
+namespace WorkingWithEFCore.AutoGen
+{
+    public partial class Northwind : DbContext
+    {
+        public Northwind()
+        {
+        }
+
+        public Northwind(DbContextOptions<Northwind> options)
+            : base(options)
+        {
+        }
+
+        public virtual DbSet<Category> Categories { get; set; } = null!;
+        public virtual DbSet<Product> Products { get; set; } = null!;
+
+        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
+        {
+            if (!optionsBuilder.IsConfigured)
+            {
+#warning To protect potentially sensitive information in your connection string, you should move it out of source code. You can avoid scaffolding the connection string by using the Name= syntax to read it from configuration - see https://go.microsoft.com/fwlink/?linkid=2131148. For more guidance on storing connection strings, see http://go.microsoft.com/fwlink/?LinkId=723263.
+                optionsBuilder.UseSqlite("Filename=Northwind.db");
+            }
+        }
+
+        protected override void OnModelCreating(ModelBuilder modelBuilder)
+        {
+            modelBuilder.Entity<Category>(entity =>
+            {
+                entity.Property(e => e.CategoryId).ValueGeneratedNever();
+            });
+
+            modelBuilder.Entity<Product>(entity =>
+            {
+                entity.Property(e => e.ProductId).ValueGeneratedNever();
+
+                entity.Property(e => e.Discontinued).HasDefaultValueSql("0");
+
+                entity.Property(e => e.ReorderLevel).HasDefaultValueSql("0");
+
+                entity.Property(e => e.UnitPrice).HasDefaultValueSql("0");
+
+                entity.Property(e => e.UnitsInStock).HasDefaultValueSql("0");
+
+                entity.Property(e => e.UnitsOnOrder).HasDefaultValueSql("0");
+            });
+
+            OnModelCreatingPartial(modelBuilder);
+        }
+
+        partial void OnModelCreatingPartial(ModelBuilder modelBuilder);
+    }
+}

vs4win/Chapter10/WorkingWithEFCore/AutoGenModels/Product.cs

@@ -0,0 +1,41 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
+using System.ComponentModel.DataAnnotations.Schema;
+using Microsoft.EntityFrameworkCore;
+
+namespace WorkingWithEFCore.AutoGen
+{
+    [Index("CategoryId", Name = "CategoriesProducts")]
+    [Index("CategoryId", Name = "CategoryId")]
+    [Index("ProductName", Name = "ProductName")]
+    [Index("SupplierId", Name = "SupplierId")]
+    [Index("SupplierId", Name = "SuppliersProducts")]
+    public partial class Product
+    {
+        [Key]
+        public long ProductId { get; set; }
+        [Column(TypeName = "nvarchar (40)")]
+        public string ProductName { get; set; } = null!;
+        [Column(TypeName = "int")]
+        public long? SupplierId { get; set; }
+        [Column(TypeName = "int")]
+        public long? CategoryId { get; set; }
+        [Column(TypeName = "nvarchar (20)")]
+        public string? QuantityPerUnit { get; set; }
+        [Column(TypeName = "money")]
+        public byte[]? UnitPrice { get; set; }
+        [Column(TypeName = "smallint")]
+        public long? UnitsInStock { get; set; }
+        [Column(TypeName = "smallint")]
+        public long? UnitsOnOrder { get; set; }
+        [Column(TypeName = "smallint")]
+        public long? ReorderLevel { get; set; }
+        [Column(TypeName = "bit")]
+        public byte[] Discontinued { get; set; } = null!;
+
+        [ForeignKey("CategoryId")]
+        [InverseProperty("Products")]
+        public virtual Category? Category { get; set; }
+    }
+}

vs4win/Chapter10/WorkingWithEFCore/Category.cs

@@ -0,0 +1,24 @@
+using System.ComponentModel.DataAnnotations.Schema; // [Column]
+
+namespace Packt.Shared;
+
+public class Category
+{
+  // these properties map to columns in the database
+  public int CategoryId { get; set; }
+
+  public string? CategoryName { get; set; }
+
+  [Column(TypeName = "ntext")]
+  public string? Description { get; set; }
+
+  // defines a navigation property for related rows
+  public virtual ICollection<Product> Products { get; set; }
+
+  public Category()
+  {
+    // to enable developers to add products to a Category we must
+    // initialize the navigation property to an empty collection
+    Products = new HashSet<Product>();
+  }
+}

vs4win/Chapter10/WorkingWithEFCore/Northwind.cs

@@ -0,0 +1,57 @@
+using Microsoft.EntityFrameworkCore; // DbContext, DbContextOptionsBuilder
+using Microsoft.EntityFrameworkCore.Diagnostics;
+
+namespace Packt.Shared;
+
+// this manages the connection to the database
+public class Northwind : DbContext
+{
+  // these properties map to tables in the database
+  public DbSet<Category>? Categories { get; set; }
+  public DbSet<Product>? Products { get; set; }
+
+  protected override void OnConfiguring(
+    DbContextOptionsBuilder optionsBuilder)
+  {
+    string path = Path.Combine(
+      Environment.CurrentDirectory, "Northwind.db");
+
+    string connection = $"Filename={path}";
+
+    ConsoleColor previousColor = ForegroundColor;
+    ForegroundColor = ConsoleColor.DarkYellow;
+    WriteLine($"Connection: {connection}");
+    ForegroundColor = previousColor;
+
+    optionsBuilder.UseSqlite(connection);
+
+    optionsBuilder.LogTo(WriteLine, // Console
+      new[] { RelationalEventId.CommandExecuting }) 
+      .EnableSensitiveDataLogging();
+
+    optionsBuilder.UseLazyLoadingProxies();
+  }
+
+  protected override void OnModelCreating(
+    ModelBuilder modelBuilder)
+  {
+    // example of using Fluent API instead of attributes
+    // to limit the length of a category name to 15
+    modelBuilder.Entity<Category>()
+      .Property(category => category.CategoryName)
+      .IsRequired() // NOT NULL
+      .HasMaxLength(15);
+
+    if (Database.ProviderName?.Contains("Sqlite") ?? false)
+    {
+      // added to "fix" the lack of decimal support in SQLite
+      modelBuilder.Entity<Product>()
+        .Property(product => product.Cost)
+        .HasConversion<double>();
+    }
+
+    // global filter to remove discontinued products
+    modelBuilder.Entity<Product>()
+      .HasQueryFilter(p => !p.Discontinued);
+  }
+}

vs4win/Chapter10/WorkingWithEFCore/Product.cs

@@ -0,0 +1,26 @@
+using System.ComponentModel.DataAnnotations; // [Required], [StringLength]
+using System.ComponentModel.DataAnnotations.Schema; // [Column]
+
+namespace Packt.Shared;
+
+public class Product
+{
+  public int ProductId { get; set; } // primary key
+
+  [Required]
+  [StringLength(40)]
+  public string ProductName { get; set; } = null!;
+
+  [Column("UnitPrice", TypeName = "money")]
+  public decimal? Cost { get; set; } // property name != column name
+
+  [Column("UnitsInStock")]
+  public short? Stock { get; set; }
+
+  public bool Discontinued { get; set; }
+
+  // these two define the foreign key relationship
+  // to the Categories table
+  public int CategoryId { get; set; }
+  public virtual Category Category { get; set; } = null!;
+}

vs4win/Chapter10/WorkingWithEFCore/Program.Helpers.cs

@@ -0,0 +1,28 @@
+partial class Program
+{
+  static void SectionTitle(string title)
+  {
+    ConsoleColor previousColor = ForegroundColor;
+    ForegroundColor = ConsoleColor.Yellow;
+    WriteLine("*");
+    WriteLine($"* {title}");
+    WriteLine("*");
+    ForegroundColor = previousColor;
+  }
+
+  static void Fail(string message)
+  {
+    ConsoleColor previousColor = ForegroundColor;
+    ForegroundColor = ConsoleColor.Red;
+    WriteLine($"Fail > {message}");
+    ForegroundColor = previousColor;
+  }
+
+  static void Info(string message)
+  {
+    ConsoleColor previousColor = ForegroundColor;
+    ForegroundColor = ConsoleColor.Cyan;
+    WriteLine($"Info > {message}");
+    ForegroundColor = previousColor;
+  }
+}

vs4win/Chapter10/WorkingWithEFCore/Program.Modifications.cs

@@ -0,0 +1,107 @@
+using Microsoft.EntityFrameworkCore.ChangeTracking; // EntityEntry<T>
+using Microsoft.EntityFrameworkCore.Storage; // IDbContextTransaction
+using Packt.Shared;
+
+partial class Program
+{
+  static void ListProducts(int? productIdToHighlight = null)
+  {
+    using (Northwind db = new())
+    {
+      if ((db.Products is null) || (db.Products.Count() == 0))
+      {
+        Fail("There are no products.");
+        return;
+      }
+
+      WriteLine("| {0,-3} | {1,-35} | {2,8} | {3,5} | {4} |",
+        "Id", "Product Name", "Cost", "Stock", "Disc.");
+
+      foreach (Product p in db.Products)
+      {
+        ConsoleColor previousColor = ForegroundColor;
+
+        if (productIdToHighlight == p.ProductId)
+        {
+          ForegroundColor = ConsoleColor.Green;
+        }
+
+        WriteLine("| {0:000} | {1,-35} | {2,8:$#,##0.00} | {3,5} | {4} |",
+          p.ProductId, p.ProductName, p.Cost, p.Stock, p.Discontinued);
+
+        ForegroundColor = previousColor;
+      }
+    }
+  }
+
+  static (int affected, int productId) AddProduct(
+    int categoryId, string productName, decimal? price)
+  {
+    using (Northwind db = new())
+    {
+      Product p = new()
+      {
+        CategoryId = categoryId,
+        ProductName = productName,
+        Cost = price,
+        Stock = 72
+      };
+
+      // set product as added in change tracking
+      EntityEntry<Product> entity = db.Products.Add(p);
+      WriteLine($"State: {entity.State}, ProductId: {p.ProductId}");
+
+      // save tracked change to database
+      int affected = db.SaveChanges();
+      WriteLine($"State: {entity.State}, ProductId: {p.ProductId}");
+
+      return (affected, p.ProductId);
+    }
+  }
+
+  static (int affected, int productId) IncreaseProductPrice(
+    string productNameStartsWith, decimal amount)
+  {
+    using (Northwind db = new())
+    {
+      // get first product whose name starts with name
+      Product updateProduct = db.Products.First(
+        p => p.ProductName.StartsWith(productNameStartsWith));
+
+      updateProduct.Cost += amount;
+
+      int affected = db.SaveChanges();
+
+      return (affected, updateProduct.ProductId);
+    }
+  }
+
+  static int DeleteProducts(string productNameStartsWith)
+  {
+    using (Northwind db = new())
+    {
+      using (IDbContextTransaction t = db.Database.BeginTransaction())
+      {
+        WriteLine("Transaction isolation level: {0}",
+          arg0: t.GetDbTransaction().IsolationLevel);
+
+        IQueryable<Product>? products = db.Products?.Where(
+        p => p.ProductName.StartsWith(productNameStartsWith));
+
+        if (products is null)
+        {
+          WriteLine("No products found to delete.");
+          return 0;
+        }
+        else
+        {
+          db.Products.RemoveRange(products);
+        }
+
+        int affected = db.SaveChanges();
+        t.Commit();
+        return affected;
+      }
+    }
+  }
+}

vs4win/Chapter10/WorkingWithEFCore/Program.Queries.cs

@@ -0,0 +1,199 @@
+using Microsoft.EntityFrameworkCore; // Include extension method
+using Microsoft.EntityFrameworkCore.ChangeTracking; // CollectionEntry
+using Packt.Shared; // Northwind, Category, Product
+
+partial class Program
+{
+  static void QueryingCategories()
+  {
+    using (Northwind db = new())
+    {
+      SectionTitle("Categories and how many products they have:");
+
+      // a query to get all categories and their related products
+      IQueryable<Category>? categories;
+      // = db.Categories;
+      // .Include(c => c.Products);
+
+      db.ChangeTracker.LazyLoadingEnabled = false;
+
+      Write("Enable eager loading? (Y/N): ");
+      bool eagerLoading = (ReadKey(intercept: true).Key == ConsoleKey.Y);
+      bool explicitLoading = false;
+      WriteLine();
+
+      if (eagerLoading)
+      {
+        categories = db.Categories?.Include(c => c.Products);
+      }
+      else
+      {
+        categories = db.Categories;
+        Write("Enable explicit loading? (Y/N): ");
+        explicitLoading = (ReadKey(intercept: true).Key == ConsoleKey.Y);
+        WriteLine();
+      }
+
+      if (categories is null)
+      {
+        Fail("No categories found.");
+        return;
+      }
+
+      // execute query and enumerate results
+      foreach (Category c in categories)
+      {
+        if (explicitLoading)
+        {
+          Write($"Explicitly load products for {c.CategoryName}? (Y/N): ");
+          ConsoleKeyInfo key = ReadKey(intercept: true);
+          WriteLine();
+
+          if (key.Key == ConsoleKey.Y)
+          {
+            CollectionEntry<Category, Product> products =
+              db.Entry(c).Collection(c2 => c2.Products);
+
+            if (!products.IsLoaded) products.Load();
+          }
+        }
+
+        WriteLine($"{c.CategoryName} has {c.Products.Count} products.");
+      }
+    }
+  }
+
+  static void FilteredIncludes()
+  {
+    using (Northwind db = new())
+    {
+      SectionTitle("Products with a minimum number of units in stock.");
+
+      string? input;
+      int stock;
+
+      do
+      {
+        Write("Enter a minimum for units in stock: ");
+        input = ReadLine();
+      } while (!int.TryParse(input, out stock));
+
+      IQueryable<Category>? categories = db.Categories?
+        .Include(c => c.Products.Where(p => p.Stock >= stock));
+
+      if (categories is null)
+      {
+        Fail("No categories found.");
+        return;
+      }
+
+      Info($"ToQueryString: {categories.ToQueryString()}");
+
+      foreach (Category c in categories)
+      {
+        WriteLine($"{c.CategoryName} has {c.Products.Count} products with a minimum of {stock} units in stock.");
+        foreach (Product p in c.Products)
+        {
+          WriteLine($"  {p.ProductName} has {p.Stock} units in stock.");
+        }
+      }
+    }
+  }
+
+  static void QueryingProducts()
+  {
+    using (Northwind db = new())
+    {
+      SectionTitle("Products that cost more than a price, highest at top.");
+
+      string? input;
+      decimal price;
+
+      do
+      {
+        Write("Enter a product price: ");
+        input = ReadLine();
+      } while (!decimal.TryParse(input, out price));
+
+      IQueryable<Product>? products = db.Products?
+        .Where(product => product.Cost > price)
+        .OrderByDescending(product => product.Cost);
+
+      if (products is null)
+      {
+        Fail("No products found.");
+        return;
+      }
+
+      Info($"ToQueryString: {products.ToQueryString()}");
+
+      foreach (Product p in products)
+      {
+        WriteLine(
+          "{0}: {1} costs {2:$#,##0.00} and has {3} in stock.",
+          p.ProductId, p.ProductName, p.Cost, p.Stock);
+      }
+    }
+  }
+
+  static void QueryingWithLike()
+  {
+    using (Northwind db = new())
+    {
+      SectionTitle("Pattern matching with LIKE.");
+
+      Write("Enter part of a product name: ");
+      string? input = ReadLine();
+
+      if (string.IsNullOrWhiteSpace(input))
+      {
+        Fail("You did not enter part of a product name.");
+        return;
+      }
+
+      IQueryable<Product>? products = db.Products?
+        .Where(p => EF.Functions.Like(p.ProductName, $"%{input}%"));
+
+      if (products is null)
+      {
+        Fail("No products found.");
+        return;
+      }
+
+      foreach (Product p in products)
+      {
+        WriteLine("{0} has {1} units in stock. Discontinued? {2}",
+          p.ProductName, p.Stock, p.Discontinued);
+      }
+    }
+  }
+
+  static void GetRandomProduct()
+  {
+    using (Northwind db = new())
+    {
+      SectionTitle("Get a random product.");
+
+      int? rowCount = db.Products?.Count();
+
+      if (rowCount == null)
+      {
+        Fail("Products table is empty.");
+        return;
+      }
+
+      Product? p = db.Products?.FirstOrDefault(
+        p => p.ProductId == (int)(EF.Functions.Random() * rowCount));
+
+      if (p == null)
+      {
+        Fail("Product not found.");
+        return;
+      }
+
+      WriteLine($"Random product: {p.ProductId} {p.ProductName}");
+    }
+  }
+
+}
+

vs4win/Chapter10/WorkingWithEFCore/Program.cs

@@ -0,0 +1,48 @@
+using Packt.Shared;
+
+/*
+Northwind db = new();
+WriteLine($"Provider: {db.Database.ProviderName}");
+*/
+
+// QueryingCategories();
+
+//FilteredIncludes();
+
+//QueryingProducts();
+
+//QueryingWithLike();
+
+//GetRandomProduct();
+
+var resultAdd = AddProduct(categoryId: 6,
+  productName: "Bob's Burgers", price: 500M);
+
+if (resultAdd.affected == 1)
+{
+  WriteLine("Add product successful.");
+}
+
+ListProducts(productIdToHighlight: resultAdd.productId);
+
+var resultUpdate = IncreaseProductPrice(
+  productNameStartsWith: "Bob", amount: 20M);
+
+if (resultUpdate.affected == 1)
+{
+  WriteLine("Increase product price successful.");
+}
+
+ListProducts(productIdToHighlight: resultUpdate.productId);
+
+WriteLine("About to delete all products whose name starts with Bob.");
+Write("Press Enter to continue: ");
+if (ReadKey(intercept: true).Key == ConsoleKey.Enter)
+{
+  int deleted = DeleteProducts(productNameStartsWith: "Bob");
+  WriteLine($"{deleted} product(s) were deleted.");
+}
+else
+{
+  WriteLine("Delete was cancelled.");
+}

vs4win/Chapter10/WorkingWithEFCore/WorkingWithEFCore.csproj

@@ -0,0 +1,26 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net7.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+	<ItemGroup>
+		<Using Include="System.Console" Static="true" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="7.0.0-*" />
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="7.0.0-*" />
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Proxies" Version="7.0.0-*" />
+	</ItemGroup>
+
+	<ItemGroup>
+	  <None Update="Northwind.db">
+	    <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+	  </None>
+	</ItemGroup>
+
+</Project>

vscode/Chapter10/Ch10Ex02DataSerialization/Category.cs

@@ -0,0 +1,24 @@
+using System.ComponentModel.DataAnnotations.Schema; // [Column]
+
+namespace Packt.Shared;
+
+public class Category
+{
+  // these properties map to columns in the database
+  public int CategoryId { get; set; }
+
+  public string? CategoryName { get; set; }
+
+  [Column(TypeName = "ntext")]
+  public string? Description { get; set; }
+
+  // defines a navigation property for related rows
+  public virtual ICollection<Product> Products { get; set; }
+
+  public Category()
+  {
+    // to enable developers to add products to a Category we must
+    // initialize the navigation property to an empty collection
+    Products = new HashSet<Product>();
+  }
+}

vscode/Chapter10/Ch10Ex02DataSerialization/Ch10Ex02DataSerialization.csproj

@@ -0,0 +1,24 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net7.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+	<ItemGroup>
+		<Using Include="System.Console" Static="true" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="7.0.0-*" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<None Update="Northwind.db">
+			<CopyToOutputDirectory>Always</CopyToOutputDirectory>
+		</None>
+	</ItemGroup>
+
+</Project>

vscode/Chapter10/Ch10Ex02DataSerialization/Northwind.cs

@@ -0,0 +1,47 @@
+using Microsoft.EntityFrameworkCore; // DbContext, DbContextOptionsBuilder
+using Microsoft.EntityFrameworkCore.Diagnostics;
+
+namespace Packt.Shared;
+
+// this manages the connection to the database
+public class Northwind : DbContext
+{
+  // these properties map to tables in the database
+  public DbSet<Category>? Categories { get; set; }
+  public DbSet<Product>? Products { get; set; }
+
+  protected override void OnConfiguring(
+    DbContextOptionsBuilder optionsBuilder)
+  {
+    string path = Path.Combine(
+      Environment.CurrentDirectory, "Northwind.db");
+
+    string connection = $"Filename={path}";
+
+    ConsoleColor previousColor = ForegroundColor;
+    ForegroundColor = ConsoleColor.DarkYellow;
+    WriteLine($"Connection: {connection}");
+    ForegroundColor = previousColor;
+
+    optionsBuilder.UseSqlite(connection);
+  }
+
+  protected override void OnModelCreating(
+    ModelBuilder modelBuilder)
+  {
+    // example of using Fluent API instead of attributes
+    // to limit the length of a category name to 15
+    modelBuilder.Entity<Category>()
+      .Property(category => category.CategoryName)
+      .IsRequired() // NOT NULL
+      .HasMaxLength(15);
+
+    if (Database.ProviderName?.Contains("Sqlite") ?? false)
+    {
+      // added to "fix" the lack of decimal support in SQLite
+      modelBuilder.Entity<Product>()
+        .Property(product => product.Cost)
+        .HasConversion<double>();
+    }
+  }
+}

vscode/Chapter10/Ch10Ex02DataSerialization/Product.cs

@@ -0,0 +1,26 @@
+using System.ComponentModel.DataAnnotations; // [Required], [StringLength]
+using System.ComponentModel.DataAnnotations.Schema; // [Column]
+
+namespace Packt.Shared;
+
+public class Product
+{
+  public int ProductId { get; set; } // primary key
+
+  [Required]
+  [StringLength(40)]
+  public string ProductName { get; set; } = null!;
+
+  [Column("UnitPrice", TypeName = "money")]
+  public decimal? Cost { get; set; } // property name != column name
+
+  [Column("UnitsInStock")]
+  public short? Stock { get; set; }
+
+  public bool Discontinued { get; set; }
+
+  // these two define the foreign key relationship
+  // to the Categories table
+  public int CategoryId { get; set; }
+  public virtual Category Category { get; set; } = null!;
+}

vscode/Chapter10/Ch10Ex02DataSerialization/Program.Functions.cs

@@ -0,0 +1,163 @@
+using System.Xml; // XmlWriter
+using System.Text.Json; // Utf8JsonWriter, JsonWriterOptions
+using Packt.Shared; // Category, Product
+
+using static System.IO.Path;
+using static System.Environment;
+
+// we want to easily show the difference between outputting
+// XML using elements or attributes so we will define a 
+// delegate to reference the two different methods.
+
+delegate void WriteDataDelegate(string name, string? value);
+
+partial class Program
+{
+  static void GenerateXmlFile(
+    IQueryable<Category> categories, bool useAttributes = true)
+  {
+    string which = useAttributes ? "attibutes" : "elements";
+
+    string xmlFile = $"categories-and-products-using-{which}.xml";
+
+    using (FileStream xmlStream = File.Create(
+      Combine(CurrentDirectory, xmlFile)))
+    {
+      using (XmlWriter xml = XmlWriter.Create(xmlStream,
+        new XmlWriterSettings { Indent = true }))
+      {
+
+        WriteDataDelegate writeMethod;
+
+        if (useAttributes)
+        {
+          writeMethod = xml.WriteAttributeString;
+        }
+        else // use elements
+        {
+          writeMethod = xml.WriteElementString;
+        }
+
+        xml.WriteStartDocument();
+        xml.WriteStartElement("categories");
+
+        foreach (Category c in categories)
+        {
+          xml.WriteStartElement("category");
+          writeMethod("id", c.CategoryId.ToString());
+          writeMethod("name", c.CategoryName);
+          writeMethod("desc", c.Description);
+          writeMethod("product_count", c.Products.Count.ToString());
+          xml.WriteStartElement("products");
+
+          foreach (Product p in c.Products)
+          {
+            xml.WriteStartElement("product");
+
+            writeMethod("id", p.ProductId.ToString());
+            writeMethod("name", p.ProductName);
+            writeMethod("cost", p.Cost is null ? "0" : p.Cost.Value.ToString());
+            writeMethod("stock", p.Stock.ToString());
+            writeMethod("discontinued", p.Discontinued.ToString());
+
+            xml.WriteEndElement(); // </product>
+          }
+          xml.WriteEndElement(); // </products>
+          xml.WriteEndElement(); // </category>
+        }
+        xml.WriteEndElement(); // </categories>
+      }
+    }
+
+    WriteLine("{0} contains {1:N0} bytes.",
+      arg0: xmlFile,
+      arg1: new FileInfo(xmlFile).Length);
+  }
+
+  static void GenerateCsvFile(IQueryable<Category> categories)
+  {
+    string csvFile = "categories-and-products.csv";
+
+    using (FileStream csvStream = File.Create(Combine(CurrentDirectory, csvFile)))
+    {
+      using (StreamWriter csv = new(csvStream))
+      {
+
+        csv.WriteLine("CategoryId,CategoryName,Description,ProductId,ProductName,Cost,Stock,Discontinued");
+
+        foreach (Category c in categories)
+        {
+          foreach (Product p in c.Products)
+          {
+            csv.Write("{0},\"{1}\",\"{2}\",",
+              arg0: c.CategoryId,
+              arg1: c.CategoryName,
+              arg2: c.Description);
+
+            csv.Write("{0},\"{1}\",{2},",
+              arg0: p.ProductId,
+              arg1: p.ProductName,
+              arg2: p.Cost is null ? 0 : p.Cost.Value);
+
+            csv.WriteLine("{0},{1}",
+              arg0: p.Stock,
+              arg1: p.Discontinued);
+          }
+        }
+      }
+    }
+
+    WriteLine("{0} contains {1:N0} bytes.",
+      arg0: csvFile,
+      arg1: new FileInfo(csvFile).Length);
+  }
+
+  static void GenerateJsonFile(IQueryable<Category> categories)
+  {
+    string jsonFile = "categories-and-products.json";
+
+    using (FileStream jsonStream = File.Create(Combine(CurrentDirectory, jsonFile)))
+    {
+      using (Utf8JsonWriter json = new(jsonStream,
+        new JsonWriterOptions { Indented = true }))
+      {
+        json.WriteStartObject();
+        json.WriteStartArray("categories");
+
+        foreach (Category c in categories)
+        {
+          json.WriteStartObject();
+
+          json.WriteNumber("id", c.CategoryId);
+          json.WriteString("name", c.CategoryName);
+          json.WriteString("desc", c.Description);
+          json.WriteNumber("product_count", c.Products.Count);
+
+          json.WriteStartArray("products");
+
+          foreach (Product p in c.Products)
+          {
+            json.WriteStartObject();
+
+            json.WriteNumber("id", p.ProductId);
+            json.WriteString("name", p.ProductName);
+            json.WriteNumber("cost", p.Cost is null ? 0 : p.Cost.Value);
+            json.WriteNumber("stock", p.Stock is null ? 0 : p.Stock.Value);
+            json.WriteBoolean("discontinued", p.Discontinued);
+
+            json.WriteEndObject(); // product
+          }
+          json.WriteEndArray(); // products
+          json.WriteEndObject(); // category
+        }
+        json.WriteEndArray(); // categories
+        json.WriteEndObject();
+      }
+    }
+
+    WriteLine("{0} contains {1:N0} bytes.",
+      arg0: jsonFile,
+      arg1: new FileInfo(jsonFile).Length);
+  }
+}
+

vscode/Chapter10/Ch10Ex02DataSerialization/Program.cs

@@ -0,0 +1,23 @@
+using Microsoft.EntityFrameworkCore; // Include extension method
+using Packt.Shared; // Northwind, Category, Product
+
+WriteLine("Creating four files containing serialized categories and products.");
+
+using (Northwind db = new())
+{
+  // a query to get all categories and their related products 
+  IQueryable<Category>? categories = db.Categories?.Include(c => c.Products);
+
+  if (categories is null)
+  {
+    WriteLine("No categories found.");
+    return;
+  }
+
+  GenerateXmlFile(categories);
+  GenerateXmlFile(categories, useAttributes: false);
+  GenerateCsvFile(categories);
+  GenerateJsonFile(categories);
+
+  WriteLine($"Current directory: {Environment.CurrentDirectory}");
+}

vscode/Chapter10/Chapter10.code-workspace

@@ -0,0 +1,13 @@
+{
+	"folders": [
+		{
+			"path": "WorkingWithEFCore"
+		},
+		{
+			"path": "CoursesAndStudents"
+		},
+		{
+			"path": "Ch10Ex02DataSerialization"
+		}
+	]
+}

vscode/Chapter10/CoursesAndStudents/Academy.cs

@@ -0,0 +1,91 @@
+using Microsoft.EntityFrameworkCore; // DbContext, DbSet<T>
+
+namespace Packt.Shared;
+
+public class Academy : DbContext
+{
+  public DbSet<Student>? Students { get; set; }
+  public DbSet<Course>? Courses { get; set; }
+
+  protected override void OnConfiguring(
+    DbContextOptionsBuilder optionsBuilder)
+  {
+    string path = Path.Combine(
+      Environment.CurrentDirectory, "Academy.db");
+
+    string connection = $"Filename={path}";
+    // string connection = @"Data Source=.;Initial Catalog=Academy;Integrated Security=true;MultipleActiveResultSets=true;";
+
+    WriteLine($"Connection: {connection}");
+
+    optionsBuilder.UseSqlite(connection);
+    // optionsBuilder.UseSqlServer(connection);
+  }
+
+  protected override void OnModelCreating(ModelBuilder modelBuilder)
+  {
+    // Fluent API validation rules
+    modelBuilder.Entity<Student>()
+      .Property(s => s.LastName).HasMaxLength(30).IsRequired();
+
+    // populate database with sample data
+    Student alice = new()
+    {
+      StudentId = 1,
+      FirstName = "Alice",
+      LastName = "Jones"
+    };
+
+    Student bob = new()
+    {
+      StudentId = 2,
+      FirstName = "Bob",
+      LastName = "Smith"
+    };
+
+    Student cecilia = new()
+    {
+      StudentId = 3,
+      FirstName = "Cecilia",
+      LastName = "Ramirez"
+    };
+
+    Course csharp = new()
+    {
+      CourseId = 1,
+      Title = "C# 10 and .NET 6"
+    };
+
+    Course webdev = new()
+    {
+      CourseId = 2,
+      Title = "Web Development"
+    };
+    
+    Course python = new()
+    {
+      CourseId = 3,
+      Title = "Python for Beginners"
+    };
+
+    modelBuilder.Entity<Student>()
+      .HasData(alice, bob, cecilia);
+
+    modelBuilder.Entity<Course>()
+      .HasData(csharp, webdev, python);
+    
+    modelBuilder.Entity<Course>()
+      .HasMany(c => c.Students)
+      .WithMany(s => s.Courses)
+      .UsingEntity(e => e.HasData(
+        // all students signed up for C# course
+        new { CoursesCourseId = 1, StudentsStudentId = 1 },
+        new { CoursesCourseId = 1, StudentsStudentId = 2 },
+        new { CoursesCourseId = 1, StudentsStudentId = 3 },
+        // only Bob signed up for Web Dev
+        new { CoursesCourseId = 2, StudentsStudentId = 2 },
+        // only Cecilia signed up for Python
+        new { CoursesCourseId = 3, StudentsStudentId = 3 }
+      ));
+  }
+}

vscode/Chapter10/CoursesAndStudents/Course.cs

@@ -0,0 +1,14 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace Packt.Shared;
+
+public class Course
+{
+  public int CourseId { get; set; }
+
+  [Required]
+  [StringLength(60)]
+  public string? Title { get; set; }
+
+  public ICollection<Student>? Students { get; set; }
+}

vscode/Chapter10/CoursesAndStudents/CoursesAndStudents.csproj

@@ -0,0 +1,19 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net7.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+	<ItemGroup>
+		<Using Include="System.Console" Static="true" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="7.0.0-*" />
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="7.0.0-*" />
+	</ItemGroup>
+
+</Project>

vscode/Chapter10/CoursesAndStudents/Program.cs

@@ -0,0 +1,25 @@
+using Microsoft.EntityFrameworkCore; // for GenerateCreateScript()
+using Packt.Shared; // Academy
+
+using (Academy a = new())
+{
+  bool deleted = await a.Database.EnsureDeletedAsync();
+  WriteLine($"Database deleted: {deleted}");
+
+  bool created = await a.Database.EnsureCreatedAsync();
+  WriteLine($"Database created: {created}");
+
+  WriteLine("SQL script used to create database:");
+  WriteLine(a.Database.GenerateCreateScript());
+
+  foreach (Student s in a.Students.Include(s => s.Courses))
+  {
+    WriteLine("{0} {1} attends the following {2} courses:",
+      s.FirstName, s.LastName, s.Courses.Count);
+
+    foreach (Course c in s.Courses)
+    {
+      WriteLine($"  {c.Title}");
+    }
+  }
+}

vscode/Chapter10/CoursesAndStudents/Student.cs

@@ -0,0 +1,9 @@
+namespace Packt.Shared;
+
+public class Student
+{
+  public int StudentId { get; set; }
+  public string? FirstName { get; set; }
+  public string? LastName { get; set; }
+  public ICollection<Course>? Courses { get; set; }
+}

vscode/Chapter10/WorkingWithEFCore/AutoGenModels/Category.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
+using System.ComponentModel.DataAnnotations.Schema;
+using Microsoft.EntityFrameworkCore;
+
+namespace WorkingWithEFCore.AutoGen
+{
+    [Index("CategoryName", Name = "CategoryName")]
+    public partial class Category
+    {
+        public Category()
+        {
+            Products = new HashSet<Product>();
+        }
+
+        [Key]
+        public long CategoryId { get; set; }
+        [Column(TypeName = "nvarchar (15)")]
+        public string CategoryName { get; set; } = null!;
+        [Column(TypeName = "ntext")]
+        public string? Description { get; set; }
+        [Column(TypeName = "image")]
+        public byte[]? Picture { get; set; }
+
+        [InverseProperty("Category")]
+        public virtual ICollection<Product> Products { get; set; }
+    }
+}

vscode/Chapter10/WorkingWithEFCore/AutoGenModels/Northwind.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata;
+
+namespace WorkingWithEFCore.AutoGen
+{
+    public partial class Northwind : DbContext
+    {
+        public Northwind()
+        {
+        }
+
+        public Northwind(DbContextOptions<Northwind> options)
+            : base(options)
+        {
+        }
+
+        public virtual DbSet<Category> Categories { get; set; } = null!;
+        public virtual DbSet<Product> Products { get; set; } = null!;
+
+        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
+        {
+            if (!optionsBuilder.IsConfigured)
+            {
+#warning To protect potentially sensitive information in your connection string, you should move it out of source code. You can avoid scaffolding the connection string by using the Name= syntax to read it from configuration - see https://go.microsoft.com/fwlink/?linkid=2131148. For more guidance on storing connection strings, see http://go.microsoft.com/fwlink/?LinkId=723263.
+                optionsBuilder.UseSqlite("Filename=Northwind.db");
+            }
+        }
+
+        protected override void OnModelCreating(ModelBuilder modelBuilder)
+        {
+            modelBuilder.Entity<Category>(entity =>
+            {
+                entity.Property(e => e.CategoryId).ValueGeneratedNever();
+            });
+
+            modelBuilder.Entity<Product>(entity =>
+            {
+                entity.Property(e => e.ProductId).ValueGeneratedNever();
+
+                entity.Property(e => e.Discontinued).HasDefaultValueSql("0");
+
+                entity.Property(e => e.ReorderLevel).HasDefaultValueSql("0");
+
+                entity.Property(e => e.UnitPrice).HasDefaultValueSql("0");
+
+                entity.Property(e => e.UnitsInStock).HasDefaultValueSql("0");
+
+                entity.Property(e => e.UnitsOnOrder).HasDefaultValueSql("0");
+            });
+
+            OnModelCreatingPartial(modelBuilder);
+        }
+
+        partial void OnModelCreatingPartial(ModelBuilder modelBuilder);
+    }
+}

vscode/Chapter10/WorkingWithEFCore/AutoGenModels/Product.cs

@@ -0,0 +1,41 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
+using System.ComponentModel.DataAnnotations.Schema;
+using Microsoft.EntityFrameworkCore;
+
+namespace WorkingWithEFCore.AutoGen
+{
+    [Index("CategoryId", Name = "CategoriesProducts")]
+    [Index("CategoryId", Name = "CategoryId")]
+    [Index("ProductName", Name = "ProductName")]
+    [Index("SupplierId", Name = "SupplierId")]
+    [Index("SupplierId", Name = "SuppliersProducts")]
+    public partial class Product
+    {
+        [Key]
+        public long ProductId { get; set; }
+        [Column(TypeName = "nvarchar (40)")]
+        public string ProductName { get; set; } = null!;
+        [Column(TypeName = "int")]
+        public long? SupplierId { get; set; }
+        [Column(TypeName = "int")]
+        public long? CategoryId { get; set; }
+        [Column(TypeName = "nvarchar (20)")]
+        public string? QuantityPerUnit { get; set; }
+        [Column(TypeName = "money")]
+        public byte[]? UnitPrice { get; set; }
+        [Column(TypeName = "smallint")]
+        public long? UnitsInStock { get; set; }
+        [Column(TypeName = "smallint")]
+        public long? UnitsOnOrder { get; set; }
+        [Column(TypeName = "smallint")]
+        public long? ReorderLevel { get; set; }
+        [Column(TypeName = "bit")]
+        public byte[] Discontinued { get; set; } = null!;
+
+        [ForeignKey("CategoryId")]
+        [InverseProperty("Products")]
+        public virtual Category? Category { get; set; }
+    }
+}

vscode/Chapter10/WorkingWithEFCore/Category.cs

@@ -0,0 +1,24 @@
+using System.ComponentModel.DataAnnotations.Schema; // [Column]
+
+namespace Packt.Shared;
+
+public class Category
+{
+  // these properties map to columns in the database
+  public int CategoryId { get; set; }
+
+  public string? CategoryName { get; set; }
+
+  [Column(TypeName = "ntext")]
+  public string? Description { get; set; }
+
+  // defines a navigation property for related rows
+  public virtual ICollection<Product> Products { get; set; }
+
+  public Category()
+  {
+    // to enable developers to add products to a Category we must
+    // initialize the navigation property to an empty collection
+    Products = new HashSet<Product>();
+  }
+}

vscode/Chapter10/WorkingWithEFCore/Northwind.cs

@@ -0,0 +1,57 @@
+using Microsoft.EntityFrameworkCore; // DbContext, DbContextOptionsBuilder
+using Microsoft.EntityFrameworkCore.Diagnostics;
+
+namespace Packt.Shared;
+
+// this manages the connection to the database
+public class Northwind : DbContext
+{
+  // these properties map to tables in the database
+  public DbSet<Category>? Categories { get; set; }
+  public DbSet<Product>? Products { get; set; }
+
+  protected override void OnConfiguring(
+    DbContextOptionsBuilder optionsBuilder)
+  {
+    string path = Path.Combine(
+      Environment.CurrentDirectory, "Northwind.db");
+
+    string connection = $"Filename={path}";
+
+    ConsoleColor previousColor = ForegroundColor;
+    ForegroundColor = ConsoleColor.DarkYellow;
+    WriteLine($"Connection: {connection}");
+    ForegroundColor = previousColor;
+
+    optionsBuilder.UseSqlite(connection);
+
+    optionsBuilder.LogTo(WriteLine, // Console
+      new[] { RelationalEventId.CommandExecuting }) 
+      .EnableSensitiveDataLogging();
+
+    optionsBuilder.UseLazyLoadingProxies();
+  }
+
+  protected override void OnModelCreating(
+    ModelBuilder modelBuilder)
+  {
+    // example of using Fluent API instead of attributes
+    // to limit the length of a category name to 15
+    modelBuilder.Entity<Category>()
+      .Property(category => category.CategoryName)
+      .IsRequired() // NOT NULL
+      .HasMaxLength(15);
+
+    if (Database.ProviderName?.Contains("Sqlite") ?? false)
+    {
+      // added to "fix" the lack of decimal support in SQLite
+      modelBuilder.Entity<Product>()
+        .Property(product => product.Cost)
+        .HasConversion<double>();
+    }
+
+    // global filter to remove discontinued products
+    modelBuilder.Entity<Product>()
+      .HasQueryFilter(p => !p.Discontinued);
+  }
+}

vscode/Chapter10/WorkingWithEFCore/Product.cs

@@ -0,0 +1,26 @@
+using System.ComponentModel.DataAnnotations; // [Required], [StringLength]
+using System.ComponentModel.DataAnnotations.Schema; // [Column]
+
+namespace Packt.Shared;
+
+public class Product
+{
+  public int ProductId { get; set; } // primary key
+
+  [Required]
+  [StringLength(40)]
+  public string ProductName { get; set; } = null!;
+
+  [Column("UnitPrice", TypeName = "money")]
+  public decimal? Cost { get; set; } // property name != column name
+
+  [Column("UnitsInStock")]
+  public short? Stock { get; set; }
+
+  public bool Discontinued { get; set; }
+
+  // these two define the foreign key relationship
+  // to the Categories table
+  public int CategoryId { get; set; }
+  public virtual Category Category { get; set; } = null!;
+}

vscode/Chapter10/WorkingWithEFCore/Program.Helpers.cs

@@ -0,0 +1,28 @@
+partial class Program
+{
+  static void SectionTitle(string title)
+  {
+    ConsoleColor previousColor = ForegroundColor;
+    ForegroundColor = ConsoleColor.Yellow;
+    WriteLine("*");
+    WriteLine($"* {title}");
+    WriteLine("*");
+    ForegroundColor = previousColor;
+  }
+
+  static void Fail(string message)
+  {
+    ConsoleColor previousColor = ForegroundColor;
+    ForegroundColor = ConsoleColor.Red;
+    WriteLine($"Fail > {message}");
+    ForegroundColor = previousColor;
+  }
+
+  static void Info(string message)
+  {
+    ConsoleColor previousColor = ForegroundColor;
+    ForegroundColor = ConsoleColor.Cyan;
+    WriteLine($"Info > {message}");
+    ForegroundColor = previousColor;
+  }
+}

vscode/Chapter10/WorkingWithEFCore/Program.Modifications.cs

@@ -0,0 +1,107 @@
+using Microsoft.EntityFrameworkCore.ChangeTracking; // EntityEntry<T>
+using Microsoft.EntityFrameworkCore.Storage; // IDbContextTransaction
+using Packt.Shared;
+
+partial class Program
+{
+  static void ListProducts(int? productIdToHighlight = null)
+  {
+    using (Northwind db = new())
+    {
+      if ((db.Products is null) || (db.Products.Count() == 0))
+      {
+        Fail("There are no products.");
+        return;
+      }
+
+      WriteLine("| {0,-3} | {1,-35} | {2,8} | {3,5} | {4} |",
+        "Id", "Product Name", "Cost", "Stock", "Disc.");
+
+      foreach (Product p in db.Products)
+      {
+        ConsoleColor previousColor = ForegroundColor;
+
+        if (productIdToHighlight == p.ProductId)
+        {
+          ForegroundColor = ConsoleColor.Green;
+        }
+
+        WriteLine("| {0:000} | {1,-35} | {2,8:$#,##0.00} | {3,5} | {4} |",
+          p.ProductId, p.ProductName, p.Cost, p.Stock, p.Discontinued);
+
+        ForegroundColor = previousColor;
+      }
+    }
+  }
+
+  static (int affected, int productId) AddProduct(
+    int categoryId, string productName, decimal? price)
+  {
+    using (Northwind db = new())
+    {
+      Product p = new()
+      {
+        CategoryId = categoryId,
+        ProductName = productName,
+        Cost = price,
+        Stock = 72
+      };
+
+      // set product as added in change tracking
+      EntityEntry<Product> entity = db.Products.Add(p);
+      WriteLine($"State: {entity.State}, ProductId: {p.ProductId}");
+
+      // save tracked change to database
+      int affected = db.SaveChanges();
+      WriteLine($"State: {entity.State}, ProductId: {p.ProductId}");
+
+      return (affected, p.ProductId);
+    }
+  }
+
+  static (int affected, int productId) IncreaseProductPrice(
+    string productNameStartsWith, decimal amount)
+  {
+    using (Northwind db = new())
+    {
+      // get first product whose name starts with name
+      Product updateProduct = db.Products.First(
+        p => p.ProductName.StartsWith(productNameStartsWith));
+
+      updateProduct.Cost += amount;
+
+      int affected = db.SaveChanges();
+
+      return (affected, updateProduct.ProductId);
+    }
+  }
+
+  static int DeleteProducts(string productNameStartsWith)
+  {
+    using (Northwind db = new())
+    {
+      using (IDbContextTransaction t = db.Database.BeginTransaction())
+      {
+        WriteLine("Transaction isolation level: {0}",
+          arg0: t.GetDbTransaction().IsolationLevel);
+
+        IQueryable<Product>? products = db.Products?.Where(
+        p => p.ProductName.StartsWith(productNameStartsWith));
+
+        if (products is null)
+        {
+          WriteLine("No products found to delete.");
+          return 0;
+        }
+        else
+        {
+          db.Products.RemoveRange(products);
+        }
+
+        int affected = db.SaveChanges();
+        t.Commit();
+        return affected;
+      }
+    }
+  }
+}

vscode/Chapter10/WorkingWithEFCore/Program.Queries.cs

@@ -0,0 +1,199 @@
+using Microsoft.EntityFrameworkCore; // Include extension method
+using Microsoft.EntityFrameworkCore.ChangeTracking; // CollectionEntry
+using Packt.Shared; // Northwind, Category, Product
+
+partial class Program
+{
+  static void QueryingCategories()
+  {
+    using (Northwind db = new())
+    {
+      SectionTitle("Categories and how many products they have:");
+
+      // a query to get all categories and their related products
+      IQueryable<Category>? categories;
+      // = db.Categories;
+      // .Include(c => c.Products);
+
+      db.ChangeTracker.LazyLoadingEnabled = false;
+
+      Write("Enable eager loading? (Y/N): ");
+      bool eagerLoading = (ReadKey(intercept: true).Key == ConsoleKey.Y);
+      bool explicitLoading = false;
+      WriteLine();
+
+      if (eagerLoading)
+      {
+        categories = db.Categories?.Include(c => c.Products);
+      }
+      else
+      {
+        categories = db.Categories;
+        Write("Enable explicit loading? (Y/N): ");
+        explicitLoading = (ReadKey(intercept: true).Key == ConsoleKey.Y);
+        WriteLine();
+      }
+
+      if (categories is null)
+      {
+        Fail("No categories found.");
+        return;
+      }
+
+      // execute query and enumerate results
+      foreach (Category c in categories)
+      {
+        if (explicitLoading)
+        {
+          Write($"Explicitly load products for {c.CategoryName}? (Y/N): ");
+          ConsoleKeyInfo key = ReadKey(intercept: true);
+          WriteLine();
+
+          if (key.Key == ConsoleKey.Y)
+          {
+            CollectionEntry<Category, Product> products =
+              db.Entry(c).Collection(c2 => c2.Products);
+
+            if (!products.IsLoaded) products.Load();
+          }
+        }
+
+        WriteLine($"{c.CategoryName} has {c.Products.Count} products.");
+      }
+    }
+  }
+
+  static void FilteredIncludes()
+  {
+    using (Northwind db = new())
+    {
+      SectionTitle("Products with a minimum number of units in stock.");
+
+      string? input;
+      int stock;
+
+      do
+      {
+        Write("Enter a minimum for units in stock: ");
+        input = ReadLine();
+      } while (!int.TryParse(input, out stock));
+
+      IQueryable<Category>? categories = db.Categories?
+        .Include(c => c.Products.Where(p => p.Stock >= stock));
+
+      if (categories is null)
+      {
+        Fail("No categories found.");
+        return;
+      }
+
+      Info($"ToQueryString: {categories.ToQueryString()}");
+
+      foreach (Category c in categories)
+      {
+        WriteLine($"{c.CategoryName} has {c.Products.Count} products with a minimum of {stock} units in stock.");
+        foreach (Product p in c.Products)
+        {
+          WriteLine($"  {p.ProductName} has {p.Stock} units in stock.");
+        }
+      }
+    }
+  }
+
+  static void QueryingProducts()
+  {
+    using (Northwind db = new())
+    {
+      SectionTitle("Products that cost more than a price, highest at top.");
+
+      string? input;
+      decimal price;
+
+      do
+      {
+        Write("Enter a product price: ");
+        input = ReadLine();
+      } while (!decimal.TryParse(input, out price));
+
+      IQueryable<Product>? products = db.Products?
+        .Where(product => product.Cost > price)
+        .OrderByDescending(product => product.Cost);
+
+      if (products is null)
+      {
+        Fail("No products found.");
+        return;
+      }
+
+      Info($"ToQueryString: {products.ToQueryString()}");
+
+      foreach (Product p in products)
+      {
+        WriteLine(
+          "{0}: {1} costs {2:$#,##0.00} and has {3} in stock.",
+          p.ProductId, p.ProductName, p.Cost, p.Stock);
+      }
+    }
+  }
+
+  static void QueryingWithLike()
+  {
+    using (Northwind db = new())
+    {
+      SectionTitle("Pattern matching with LIKE.");
+
+      Write("Enter part of a product name: ");
+      string? input = ReadLine();
+
+      if (string.IsNullOrWhiteSpace(input))
+      {
+        Fail("You did not enter part of a product name.");
+        return;
+      }
+
+      IQueryable<Product>? products = db.Products?
+        .Where(p => EF.Functions.Like(p.ProductName, $"%{input}%"));
+
+      if (products is null)
+      {
+        Fail("No products found.");
+        return;
+      }
+
+      foreach (Product p in products)
+      {
+        WriteLine("{0} has {1} units in stock. Discontinued? {2}",
+          p.ProductName, p.Stock, p.Discontinued);
+      }
+    }
+  }
+
+  static void GetRandomProduct()
+  {
+    using (Northwind db = new())
+    {
+      SectionTitle("Get a random product.");
+
+      int? rowCount = db.Products?.Count();
+
+      if (rowCount == null)
+      {
+        Fail("Products table is empty.");
+        return;
+      }
+
+      Product? p = db.Products?.FirstOrDefault(
+        p => p.ProductId == (int)(EF.Functions.Random() * rowCount));
+
+      if (p == null)
+      {
+        Fail("Product not found.");
+        return;
+      }
+
+      WriteLine($"Random product: {p.ProductId} {p.ProductName}");
+    }
+  }
+
+}
+

vscode/Chapter10/WorkingWithEFCore/Program.cs

@@ -0,0 +1,48 @@
+using Packt.Shared;
+
+/*
+Northwind db = new();
+WriteLine($"Provider: {db.Database.ProviderName}");
+*/
+
+// QueryingCategories();
+
+//FilteredIncludes();
+
+//QueryingProducts();
+
+//QueryingWithLike();
+
+//GetRandomProduct();
+
+var resultAdd = AddProduct(categoryId: 6,
+  productName: "Bob's Burgers", price: 500M);
+
+if (resultAdd.affected == 1)
+{
+  WriteLine("Add product successful.");
+}
+
+ListProducts(productIdToHighlight: resultAdd.productId);
+
+var resultUpdate = IncreaseProductPrice(
+  productNameStartsWith: "Bob", amount: 20M);
+
+if (resultUpdate.affected == 1)
+{
+  WriteLine("Increase product price successful.");
+}
+
+ListProducts(productIdToHighlight: resultUpdate.productId);
+
+WriteLine("About to delete all products whose name starts with Bob.");
+Write("Press Enter to continue: ");
+if (ReadKey(intercept: true).Key == ConsoleKey.Enter)
+{
+  int deleted = DeleteProducts(productNameStartsWith: "Bob");
+  WriteLine($"{deleted} product(s) were deleted.");
+}
+else
+{
+  WriteLine("Delete was cancelled.");
+}

vscode/Chapter10/WorkingWithEFCore/WorkingWithEFCore.csproj

@@ -0,0 +1,26 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net7.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+	<ItemGroup>
+		<Using Include="System.Console" Static="true" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="7.0.0-*" />
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="7.0.0-*" />
+		<PackageReference Include="Microsoft.EntityFrameworkCore.Proxies" Version="7.0.0-*" />
+	</ItemGroup>
+
+	<ItemGroup>
+	  <None Update="Northwind.db">
+	    <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+	  </None>
+	</ItemGroup>
+
+</Project>