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30 lines
727 B
C#
30 lines
727 B
C#
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int thisCannotBeNull = 4;
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//thisCannotBeNull = null; // compile error!
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WriteLine(thisCannotBeNull);
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int? thisCouldBeNull = null;
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WriteLine(thisCouldBeNull);
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WriteLine(thisCouldBeNull.GetValueOrDefault());
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thisCouldBeNull = 7;
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WriteLine(thisCouldBeNull);
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WriteLine(thisCouldBeNull.GetValueOrDefault());
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// the actual type of int? is Nullable<int>
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Nullable<int> thisCouldAlsoBeNull = null;
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thisCouldAlsoBeNull = 9;
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WriteLine(thisCouldAlsoBeNull);
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// Declaring non-nullable variables and parameters
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Address address = new();
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address.Building = null;
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address.Street = null!; // null-forgiving operator
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address.City = "London";
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address.Region = "UK";
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WriteLine(address.Building?.Length);
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WriteLine(address.Street.Length);
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