C # delegated Learning (1)

I want to share with you how to use C # delegation today:

A delegate is a data structure that references static methods, class instances, and class instance methods. Let's take a look at the following example:

Int I = 100; // defines the number of integers.

Public Delegate string getstring (); // defines a delegate getstring, which returns the string type.

Getstring firstmethod = new getstring (I. tostring); // a delegate whose instantiation type is getstring.

Let's not talk about it. Let's look at an example. It's a simple example that everyone can understand:

View code

 Using  System;
  Using  System. Collections. Generic;
  Using  System. text;

  Namespace Wrox. procsharp. Delegates
{
  Class  Mathoperations
{
  Public     Static     Double  Multiplybytwo (  Double  Value)
{
  Return  Value  *     2 ;
}

  Public     Static     Double  Square (  Double  Value)
{
  Return  Value  *  Value;
}
}


  Delegate     Double Doubleop (  Double  X );

  Class  Mainentrypoint
{
  Static     Void  Main ()
{
Doubleop [] operations  =   
{
Mathoperations. multiplybytwo,
Mathoperations. Square
  //  New doubleop (mathoperations. multiplybytwo ),
  // New doubleop (mathoperations. Square)  
  };

  For  (  Int  I  =     0  ; I  <  Operations. length; I  ++  )
{
Console. writeline (  " Using operations [{0}]:  "  , I );
Processanddisplaynumber (Operations [I],  2.0  );
Processanddisplaynumber (Operations [I],  7.94  );
Processanddisplaynumber (Operations [I],  1.414  );
Console. writeline ();
}
Console. Readline ();
}

  Static     Void Processanddisplaynumber (doubleop action,  Double  Value)
{
  Double  Result  =  Action (value );
Console. writeline (
  "  Value is {0}, result of operation is {1}  "  , Value, result );
}
}
} 

A good way to understand the delegate is to treat the delegate as a name for the method signature and return type.

Processanddisplaynumber (Operations [I], 2.0); // indicates passing the delegate to the processanddisplaynumber () method.

I will write it here today. For more information about the many shortcomings, please consult.