winform下载网页代码

1:webClient client=new WebClient();
client.Downloadstring(地址)
client.Downloadfile(地址，保存路径)
2：后台线程dowork
3：声明委托
//江县城写道主界面（控件）
private void Meg()
{
messageBox.Show("下载成功")！
}
Action action=new Action(Meg);//这就是委托，就是将方法给
this.invoke()

一下是个具体事例：

public partial class Form1 : Form
    {
        public Form1()
        {
InitializeComponent();
        }

private void button1_Click(object sender, EventArgs e)
        {
            this.backgroundWorker1.RunWorkerAsync();
        }

private void button2_Click(object sender, EventArgs e)
        {
            MessageBox.Show("各种Info快来下载吧!");
        }

private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
        {
            for (int i = 3010; i < 3050; i++)
            {
                WebClient client = new WebClient();
                try
                {
                    client.DownloadFile(@"http://job.cnblogs.com/offer/" + i + "/", @"d:\" + i + ".html");
                }
                catch { }
            }
            //Action是委托
            Action action = new Action(msg);
            this.Invoke(action);
        }

private void msg()
        {
            MessageBox.Show("下载完成!");
        }
    }