委托与事件

1、Jiafang 的类

namespace 委托与事件Again_and_Again
{
//造一个甲方的类
public class JiaFang
{
//给甲方添加成员
private string _Word;

public string Word
{
get { return _Word; }
set { _Word = value; }
}
private string _Name;

public string Name
{
get { return _Name; }
set { _Name = value; }
}

//定义一个事件
public event WeituoHandler events;
//定义一个函数来触发这个事件
public void SayWords()
{
if(events!=null)
{
events(this, new message() {  Word="我是甲方"});
}
}

}
}

2、message的类
namespace 委托与事件Again_and_Again
{
public class message:EventArgs
{
private string _Word;

public string Word
{
get { return _Word; }
set { _Word = value; }
}
}
}

3、事件
namespace 委托与事件Again_and_Again
{
//定义一个委托
public delegate void WeituoHandler(object a,message msg);
public partial class Form1 : Form
{
JiaFang x;
public Form1()
{
InitializeComponent();
x = new JiaFang();
x.Name = "甲方";
label1.Text = x.Name;
x.events += x_events;//x的点击事件

}

void x_events(object a, message msg)
{
textBox1.Text = "你是谁";
textBox1.Text += "\t"+msg.Word;
}

private void button1_Click(object sender, EventArgs e)//Saywords按钮
{
x.SayWords();//触发函数，函数用来引发事件
}
}
}