Anonymous Method in C# with Examples

An anonymous method is a method which doesn’t contain any name which is introduced in C# 2.0. In C#, an anonymous method allows you to define a method inline without explicitly declaring a separate named method. It’s particularly useful when you need a method as a delegate parameter, such as for event handling or LINQ queries.

Here’s a basic syntax of an anonymous method:

Here’s how you declare and use interfaces in C#.

Example

// An Anonymous Method

delegate(parameters) {
  // method body
};

For example, to create an anonymous method that wrapped a fruit name and assign it to a delegate:

Example

using System;

// Define a delegate
delegate void fruitName(string name);

public class Program
{
  public static void Main(string[] arge)
  {
    // Create an anonymous method and assign it to a delegate
    fruitName fruit = delegate(string name)
    {
        Console.WriteLine("My favorite fruit is: {0}", name);
    };
    fruit("Cherry");
  }
}

Output

My favorite fruit is: Cherry

In above example:

1. delegate string fruitName(string name); declares a delegate named fruitName that takes an string parameter and display a fruit name string.

2. fruit is assigned an anonymous method that takes an string name and display a fruit name string.

3. fruit(“Cherry”); demonstrates calling the delegate with an argument Cherry, which prints My favorite fruit is: Cherry.

Create anonymous method with Outer variables

using System;

// Define a delegate
delegate void fruitName(string name);

public class Program
{
  public static void Main(string[] arge)
  {
    string like = "Kiwi";
    // Create an anonymous method and assign it to a delegate
    fruitName fruit = delegate(string name)
    {
      Console.WriteLine("My favorite fruit is: {0}", name);
      // Accessing outer aariable in anonymous method
      Console.WriteLine("I Like {0} also", like);
    };
    fruit("Cherry");
  }
}

Output

My favorite fruit is: Cherry
I Like Kiwi also

1. delegate string fruitName(string name); declares a delegate named fruitName that takes an string parameter and display a string.

2. fruit is assigned an anonymous method that takes an string name and display a fruit name string.

3. fruit(“Cherry”); demonstrates calling the delegate with an argument Cherry, which prints My favorite fruit is: Cherry.

4. In this example we are accessing an variable inside anonymous method that is declared out side the anonymous method. Such type of variables is known as Outer variables. As shown in the below example like is the outer variable.

Limitation of Anonymous Method

1. Cannot Access Ref or Out Parameters:

Ref and Out,in parameters does not access in anonymous method. This restricts their ability to modify variables declared in the outer scope.

2. Cannot Contain Jump Statement

It cannot contain jump statement like goto, break or continue.

3. Cannot Specify Access Modifiers:

Anonymous methods are always private and cannot have explicit access modifiers (public, private, internal, etc.). This limits control over visibility compared to named methods.

4. Can Be Used AS Event Handler

We can also use an anonymous method as an event handler.

5. Does Not Access UnSafe Code

An anonymous method does not access unsafe code.

6. Order of Definition Doesn’t Matter:

The order in which the parts of the partial class are defined doesn’t matter. The compiler merges them together to create a single class.

7. No Asynchronous Functionality:

Anonymous methods cannot be asynchronous (async), which limits their usage in scenarios requiring asynchronous operations like tasks and async-await patterns. Lambda expressions, on the other hand, can be async.

8. No Expression Body Syntax:

Unlike lambda expressions, anonymous methods require the full method body with {} and explicit return statements.

Thanks for read.

For more useful tutorials please visit the site: C-Sharp Tutorial and also if you find useful to this article please clap and follow the author by hitting below button.