Tutorial by Examples

The nameof operator returns the name of a code element as a string. This is useful when throwing exceptions related to method arguments and also when implementing INotifyPropertyChanged. public string SayHello(string greeted) { if (greeted == null) throw new ArgumentNullException(nam...

Expression-bodied function members allow the use of lambda expressions as member bodies. For simple members, it can result in cleaner and more readable code. Expression-bodied functions can be used for properties, indexers, methods, and operators. Properties public decimal TotalPrice => Base...

Exception filters give developers the ability to add a condition (in the form of a boolean expression) to a catch block, allowing the catch to execute only if the condition evaluates to true. Exception filters allow the propagation of debug information in the original exception, where as using an...

Introduction Properties can be initialized with the = operator after the closing }. The Coordinate class below shows the available options for initializing a property: 6.0 public class Coordinate { public int X { get; set; } = 34; // get or set auto-property with initializer public ...

Index initializers make it possible to create and initialize objects with indexes at the same time. This makes initializing Dictionaries very easy: var dict = new Dictionary<string, int>() { ["foo"] = 34, ["bar"] = 42 }; Any object that has an indexed gette...

String interpolation allows the developer to combine variables and text to form a string. Basic Example Two int variables are created: foo and bar. int foo = 34; int bar = 42; string resultString = $"The foo is {foo}, and the bar is {bar}."; Console.WriteLine(resultString); ...

It is possible to use await expression to apply await operator to Tasks or Task(Of TResult) in the catch and finally blocks in C#6. It was not possible to use the await expression in the catch and finally blocks in earlier versions due to compiler limitations. C#6 makes awaiting async tasks a lot e...

The ?. operator and ?[...] operator are called the null-conditional operator. It is also sometimes referred to by other names such as the safe navigation operator. This is useful, because if the . (member accessor) operator is applied to an expression that evaluates to null, the program will throw ...

The using static [Namespace.Type] directive allows the importing of static members of types and enumeration values. Extension methods are imported as extension methods (from just one type), not into top-level scope. 6.0 using static System.Console; using static System.ConsoleColor; using static ...

Following snippet shows an example of passing a method group (as opposed to a lambda) when a delegate is expected. Overload resolution will now resolve this instead of raising an ambiguous overload error due to the ability of C# 6 to check the return type of the method that was passed. using System...

Parentheses are now forbidden around named parameters. The following compiles in C#5, but not C#6 5.0 Console.WriteLine((value: 23)); Operands of is and as are no longer allowed to be method groups. The following compiles in C#5, but not C#6 5.0 var result = "".Any is byte; T...

Collection initialization syntax can be used when instantiating any class which implements IEnumerable and has a method named Add which takes a single parameter. In previous versions, this Add method had to be an instance method on the class being initialized. In C#6, it can also be an extension me...

In C# 5.0 and earlier the developer could only suppress warnings by number. With the introduction of Roslyn Analyzers, C# needs a way to disable warnings issued from specific libraries. With C# 6.0 the pragma directive can suppress warnings by name. Before: #pragma warning disable 0501 C# 6.0: ...