C# 11 is the latest version of the C# programming language, released in November 2021. Here are some of the top features included in C# 11:
1. Global using directives:
1. Global using directives:
You can now add a global using directive to your C# files, which means you don't need to add using statements for commonly used namespaces in every file.
// Instead of adding using statements for every file, you can use a global using directive // to import commonly used namespaces into every file in your project global using System; global using System.Collections.Generic; global using System.Linq; global using System.Text;2. Improved target-typed conditional expressions:
C# 11 allows for more flexible use of target-typed conditional expressions, which can make your code more concise and readable.
// C# 11 allows for more flexible use of target-typed conditional expressions // Here's an example that uses a target-typed conditional expression to check if a value is null object? nullableObject = null; string result = nullableObject is null ? "Object is null" : "Object is not null"; Console.WriteLine(result);3. File-scoped namespaces:
With file-scoped namespaces, you can define a namespace for an entire file rather than having to include a namespace declaration for each individual class.
// With file-scoped namespaces, you can define a namespace for an entire file
// rather than having to include a namespace declaration for each individual class
namespace MyNamespace;
class MyClass
{
// Class members go here
}
4. Interpolated string improvements: Interpolated strings now support string interpolation for expressions that return values of any type, not just strings.
// Interpolated strings now support string interpolation for expressions that return values of any type
int x = 5;
string result = $"The value of x is {x}";
Console.WriteLine(result);
5. Extended support for lambda discard parameters: You can now use discard parameters in lambda expressions, which can make your code more concise and easier to read.
// You can now use discard parameters in lambda expressions List6. "and" and "or" patterns:numbers = new() { 1, 2, 3, 4, 5 }; numbers.ForEach(_ => Console.WriteLine("Hello"));
C# 11 introduces new patterns that allow for more complex pattern matching logic, including the ability to combine patterns using "and" and "or".
// C# 11 introduces new patterns that allow for more complex pattern matching logic
// including the ability to combine patterns using "and" and "or"
object obj = "Hello, world!";
if (obj is string { Length: > 5 } or null)
{
Console.WriteLine("The object is a string with length greater than 5, or null");
}
7. Improved support for global usings in .NET Standard 2.1 and earlier: Global using directives are now supported in .NET Standard 2.1 and earlier, making it easier to write cross-platform code.
// Global using directives are now supported in .NET Standard 2.1 and earlier // Here's an example of using a global using directive to import System.IO // into every file in your project global using System.IO;8. Improved support for nullability:
C# 11 includes several improvements to nullability, including better support for nullable reference types and the ability to specify nullability for parameters.
// C# 11 includes several improvements to nullability
// including better support for nullable reference types and the ability to specify nullability for parameters
void MyMethod(string? nullableString)
{
// The nullableString parameter may be null, so we need to check for null before using it
if (nullableString is not null)
{
Console.WriteLine(nullableString.ToUpper());
}
}
