What is delegation in c#

A delegate in C# is a type-safe pointer that points to a method that can be called. Its advantages include callability, code reuse, and asynchronous programming. The syntax of a delegate is public delegate void DelegateName(params Type[] parameterTypes), which can be used by declaring delegate variables, pointing to methods and calling the delegate. In the example, the delegate CalculationDelegate points to the method Add and is used to calculate the sum of 10 and 20.

The role of delegation in C

#A delegate is a type-safe pointer in C# that points to A method that can be called. Delegates can pass blocks of code as parameters, enabling callback mechanisms and other advanced design patterns.

Advantages of delegation

Delegation has the following advantages:

• Callability: Delegation can be like a method is called without knowing the method being pointed to.
• Code Reuse: Delegates allow code blocks to be passed to other objects, thereby achieving code reuse and decoupling.
• Asynchronous Programming: Delegates play a vital role in asynchronous programming and are used to handle completed method callbacks.

Syntax of delegation

The syntax of declaring a delegation is as follows:

<code class="c#">public delegate void DelegateName(params Type[] parameterTypes);</code>

Among them:

• DelegateName is the name of the delegate.
• params Type[] parameterTypes Specifies the parameter type of the delegate method.

Use of delegates

In C#, you can use delegates in the following ways:

• Declare delegate variables :

<code class="c#">DelegateName delegateVariable;</code>

• Pointing method:

<code class="c#">delegateVariable = new DelegateName(MethodName);</code>

• Calling the delegate:

<code class="c#">delegateVariable();</code>

Examples of delegates

The following example demonstrates the use of delegates in C#:

<code class="c#">public delegate int CalculationDelegate(int num1, int num2);

class Program
{
    static int Add(int num1, int num2)
    {
        return num1 + num2;
    }

    static void Main()
    {
        CalculationDelegate calculate = new CalculationDelegate(Add);
        int result = calculate(10, 20);
        Console.WriteLine($"Result: {result}");
    }
}</code>

In this example, delegates CalculationDelegate is used to point to method Add, which is then used to calculate the sum of two numbers.

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