C#中委托(delegate)是一种安全地封装方法的类型,委托是面向对象的、类型安全的。
使用委托的步骤:
1、声明委托
public delegate void DelegateHandler(string message);
2、定义委托方法
// Create a method for a delegate.
public static void DelegateMethod(string message)
{
Console.WriteLine(message);
}
3、创建委托对象,并将需要传递的函数作为参数传入
// Instantiate the delegate.
DelegateHandler handler = DelegateMethod;
或:
// Instantiate the delegate.
DelegateHandler handler = new DelegateHandler(DelegateMethod);
4、调用委托方法
// Call the delegate.
handler("Hello World");
完整示例:
using System;
using System.Collections.Generic;
using System.Text; namespace DelegateExample
{
class Program
{
public delegate void DelegateHandler(string message); public static void DelegateMethod(string message)
{
Console.WriteLine(message);
} static void Main(string[] args)
{
//DelegateHandler handler = DelegateMethod;
DelegateHandler handler = new DelegateHandler(DelegateMethod);
handler("Hello World!");
}
}
}