done with basics

2-csharp/README.md

@@ -1,33 +1,30 @@
 # C# Crash Course
 
-In this C# Crash Course, we'll go over the basics of C# so that you'll be ready to build out exciting web apps in emails 3, 4, and 5! We'll start by going through the key attributes of C#, syntax basics, and introduce you to OOP. At the end, we'll link you to some quick in-browser C# challenges so you can apply these concepts.
+In this C# Crash Course, we'll go over the basics of C# so that you'll be ready to build out exciting web apps in emails 3, 4, and 5! We'll start by going through the key attributes of C#, syntax basics, and introduce you to OOP. In each section, we'll link you to some quick in-browser C# challenges so you can apply these concepts.
 
 ## Topics you'll learn
 * Language attributes
-  * Strongly typed
-  * Compiled languages
 * Syntax basics
-  * Keywords
-  * Accessing methods
-  * Parameters
-  * Semicolons
-  * Data types
-  * Variables
-  * Arithmetic operators
-  * Booleans
 * Object Oriented Programming
-  * Records
-  * Objects
-  * Properties
-  * Methods
 
-# Let's get into it!
+---
-## Language Attributes
+
+# Language attributes
 C# is a strongly typed, compiled, object oriented language. Let's break this down.
-* In a **strongly typed** language, every variable has a defined type. Every method declaration specifies a name, the type and kind for each input parameter and for the return value.
+## Strongly typed
-* A **compiler** converts the code you write into a format that your computer can understand.After you write C# and build it, the C# compiler (called Roslyn) will analyze your code to check for any errors.
+  In a **strongly typed** language, every variable has a defined type. Some of these types include:
+  * String, "Hello world!"
+  * Char, 'a'
+  * int, 3
+  * decimal, 1.5
+  * bool, True
 
-## Syntax Basics
+## Compiler 
+  A **compiler** converts the code you write into a format that your computer can understand.After you write C# and build it, the C# compiler (called Roslyn) will analyze your code to check for any errors.
+
+---
+
+# The basics
 Here's a piece of code that will print "Hello world!" to the console.
 
 ```csharp
@@ -35,20 +32,107 @@ using System;
 
 Console.WriteLine("Hello world!");
 ```
-### Keywords
+## Keywords
 With C#, you use **keywords** like *using* and *Console*.
->Keywords are predefined, reserved identifiers that have special meanings to the compiler.
+**Keywords** are predefined, reserved identifiers that have special meanings to the compiler.
 
-### Accessing methods
+## Accessing methods
 The Dot in *Console.WriteLine* allows us to access methods and properties. In this example, **Console** is a type that represents the console window. **WriteLine** is a method of the Console type that prints a line of text to that text console.
 
-### Parameters
+## Parameters
+In this example, we use parentheses pass a string as a parameter to *Console.WriteLine*. 
 
+## Variables
+  In C#, **variables** allow you to temporarily store a value in memory. In C#, you must declare a vaiable before using it. 
+  ```csharp
+  var cSharp = "really cool";
+  ```
+  In this example, we created a string called *cSharp*. You can use the var keyword to declare local variables without explicitly giving them a type.
+  
+  Variable names can contain alphanumeric characters and underscores, but no special characters. They also cannot be keywords.
 
-...
+## Syntax cheat sheet
-## OOP
+1. Every statement is ended by a semicolon
-C# is an object-oriented language. You define types and their behavior.
+   ```csharp
-...
+   Console.WriteLine("there is a ';' at the end of this statement");
+   ```
+1. You can make comments by using 2 slashes
+   ```csharp
+   // this is a comment is C#
+   ```
+1. C# is case sensitive! For example, a variable "cat" is completely different from a variable "CAT".
+    ```csharp
+    var cat = "meow";
+    var CAT = "rawr";
+    ```
+
+1. Arithmetic operators 
+   These are probably familiar to you!
+   | symbol | what it does |
+   | --- | ------ |
+   | + | addition |
+   | - | subtraction |
+   | * | multiplication |
+   | / | division |
+   | % | remainder |
+   | ++ | increment |
+   | -- | decrement |
+
+2. Boolean expressions
+  We use booleans to compare two or more things.
+    | symbol | what it does |
+    | --- | ------ |
+    | < | less than |
+    | > | greater than |
+    | <= | less than or equal |
+    | >= | greater than or equal |
+    | == | equal |
+    | != | not equal |
+   
+---
+
+# OOP
+C# is an object-oriented language. 
+Objects are defined by **Classes**. In other words, an **Object** is an instance of a class.
+One way to think about this is that a class is like the blue prints for a house. The actual house that is built is an objects because it is an instance of this blue print.
+
+Objects inherently have attributes. In C# we call these **properties**. The attributes of a house may be the number of doors, what color the house is painted, etc.
+
+We can also define **methods** which describe what an object can do. For example, you can sell your house. 
+
+Let's look at an example House class:
+```csharp
+// The namespace declaration provides a way to logically organize your classes
+namespace Classes;
+
+public class House
+{
+  // House properties
+    public string Address { get; }
+    public int Size { get;}
+
+  // House methods
+    public void SellHouse(decimal amount, DateTime date)
+    {
+    }
+}
+```
+We can define a **constructor** to allow us to create new House objects. 
+
+```csharp
+public House(string address, int squareFeet)
+{
+    this.Address = address;
+    this.Size = squareFeet;
+}
+```
+When we create an object with **new** this constructor will be called.
+```csharp
+using Classes;
+
+// Let's create a 1500 square foot house on Candy Cane Lane
+var house = new House("123 Candy Cane Lane", 1500);
+```
 
 # Mini Challenges!
 Each of these mini challenges is designed so that you can apply C# concepts to mini coding exercises. These challenges are all sourced from Microsoft documentation and will allow you to get coding inside your browser. Easy peasy!
@@ -57,7 +141,8 @@ Each of these mini challenges is designed so that you can apply C# concepts to m
 |-| ------------------------------- | ------------------------------- | ----------- |  -------------------------------------- | - |
 1 | [Hello World](https://docs.microsoft.com/learn/modules/csharp-write-first/2-exercise-hello-world/?ns-enrollment-type=learningpath&ns-enrollment-id=learn.languages.csharp-first-steps)| N/A | 3 min |  case sensitive, strings, comments | [Intro to C# Tutorial](https://docs.microsoft.com/dotnet/csharp/tour-of-csharp/tutorials/hello-world?WT.mc_id=csharpnotebook-35129-website), [C# documentation](https://docs.microsoft.com/dotnet/csharp/) |
 2 | [Variables](https://docs.microsoft.com/learn/modules/csharp-literals-variables/6-challenge )|[Solution](https://docs.microsoft.com/learn/modules/csharp-literals-variables/7-solution)| 5 min |  variables, data types, strings, ints, decimals | [Numberic Types](https://docs.microsoft.com/dotnet/csharp/tour-of-csharp/tutorials/numbers-in-csharp?WT.mc_id=csharpnotebook-35129-website), [C# documentation](https://docs.microsoft.com/dotnet/csharp/) |
-3 | [Challenge](...)|[Solution](...)| 5 min |  topics | [Link](...) |
+3 | [Operating on Numbers](https://docs.microsoft.com/learn/modules/csharp-basic-operations/5-challenge)|[Solution](https://docs.microsoft.com/learn/modules/csharp-basic-operations/6-solution)| 2 min |  ints, decimals | [Link](...) |
+4 | [Challenge](...)|[Solution](...)| 5 min |  topics | [Link](...) |
 
 
 # Bonus and more ways to connect