Simple and small exploration of new features available in the latests C# releases.

C# 8 can be used with the .NET Framework and other targets older than .NET Core 3.0/.NET Standard 2.1 in Visual Studio 2019 (or older versions of Visual Studio if you install a Nuget package.

The language version must be set to 8.0 in the csproj file.

C# 8.0 introduces nullable reference types and non-nullable reference types that enable you to make important statements about the properties for reference type variables.

Samples in NullableReferenceType.cs
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The ability to declare more properties about reference types brings more typesafety and type soundness to your code. I consider this feature of high valuable to express input and output of functions, providing a more accurate information to API client.

A using declaration is a variable declaration preceded by the using keyword. It tells the compiler that the variable being declared should be disposed at the end of the enclosing scope. Using declaration is a declarative way to handle disposable objects instead of the classic imperative of the using statement.

Samples in UsingDeclaration.cs
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Often, a switch statement produces a value in each of its case blocks. Switch expressions enable you to use more concise expression syntax.

Samples in SwitchExpressions.cs
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Ranges and indices provide a succinct syntax for accessing single elements or ranges in a sequence. This feature should be a good replacement if you are already working with indices, therefore handling Out of range exceptions. In the examples there are scenarios like paging which can be solved by using indices and ranges but I would continue with the combination of skip + take in order to avoid the Out of range validations.

Samples in IndicesAndRanges.cs
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C# 8.0 introduces the null-coalescing assignment operator ??=. You can use the ??= operator to assign the value of its right-hand operand to its left-hand operand only if the left-hand operand evaluates to null.

Samples in NullCoalescingOperator.cs
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You can now add members to interfaces and provide an implementation for those members. This language feature enables API authors to add methods to an interface in later versions without breaking source or binary compatibility with existing implementations of that interface. It is not that bad as the interface method can only be seen when using the interface type, therefore transparent to the type which implements the interface itself. The ability which strikes me to the most is the definition of static methods in interfaces.

Samples in DefaultInterfaceMethods.cs
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