1. 从工具栏拖一个BackgroundWorker控件,设置其属性WorkerReportsProgress为true
2. 要让worker开始工作,执行如下代码:
mBackgroundWorker.RunWorkerAsync(arg);
这里有重写,如果不需要传递参数直接mBackgroundWorker.RunWorkerAsync();
3. 编辑DoWork事件代码:
e.Argument为mBackgroundWorker.RunWorkerAsync(arg);对应的参数
之所以使用进度条,肯定是有循环的,在循环中报告进度:
worker.ReportProgress(i * 100 / totalNum, obj );
其中第一个参数是当前进度的百分之多少,obj为你要传递的UserState,如果没有可以不要
4. 编辑ProgressChanged事件代码:
e.ProgressPercentage为进度的百分数,e.UserState为刚才传递过来的object
在这个事件中可以调用ui的进度条和其他控件:
mToolStripProgressBar.Value = e.ProgressPercentage;
5. 编辑RunWorkerCompleted事件代码:
工作完成了告诉ui
示例代码:一个简单的刷网页流量的小工具
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Net;
using System.Threading;
namespace shua
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
backgroundWorker1.RunWorkerAsync(textBox1.Text);
}
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
BackgroundWorker worker = (BackgroundWorker)sender;
string url = e.Argument.ToString();
int num = int.Parse(textBox2.Text);
for (int i = 0; i < num; i++)
{
if (!worker.CancellationPending)
{
WebRequest request = WebRequest.Create(url);
WebResponse response = request.GetResponse();
response.Close();
Thread.Sleep(100);
worker.ReportProgress(i * 100 / num, i);
}
}
}
private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
progressBar1.Value = e.ProgressPercentage;
label3.Text = e.UserState.ToString();
}
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
MessageBox.Show("ok");
}
}
}
.net 2.0 BackgroundWorker类详细用法
最新推荐文章于 2022-10-26 10:46:22 发布