内容发布更新时间 : 2024/12/23 21:07:05星期一 下面是文章的全部内容请认真阅读。
*
* 还有如下方法：
* CancelAsync——请求取消挂起的后台操作
* ReportProgress——引发 ProgressChanged 事件 * RunWorkerAsync——开始执行后台操作 * **/
namespace BackgroundWorkerDemo {
public partial class MainForm : Form {
private
BackgroundWorker
worker
=
BackgroundWorker(); public MainForm() {
InitializeComponent();
worker.WorkerReportsProgress = true; worker.WorkerSupportsCancellation = true; //正式做事情的地方 worker.DoWork+=new DoWorkEventHandler(DoWork);
//任务完称时要做的，比如提示等等
new
worker.ProgressChanged += new
ProgressChangedEventHandler(ProgessChanged); //任务进行时，报告进度 worker.RunWorkerCompleted
+=
new
RunWorkerCompletedEventHandler(CompleteWork); }
//调用 RunWorkerAsync 时发生
public void DoWork(object sender, DoWorkEventArgs e) {
e.Result = ComputeFibonacci(worker, e);//当ComputeFibonacci(worker, e)返回时，异步过程结束 }
//调用 ReportProgress 时发生 public
void
ProgessChanged(object
sender,
ProgressChangedEventArgs e) {
this.progressBar1.Value = e.ProgressPercentage; }
//当后台操作已完成、被取消或引发异常时发生 public
void
CompleteWork(object
sender,
RunWorkerCompletedEventArgs e) {
MessageBox.Show(\完成！\ }
private
int
ComputeFibonacci(object
DoWorkEventArgs e) {
for (int i = 0; i < 1000; i++) {
if (worker.CancellationPending) {
e.Cancel = true; } else {
worker.ReportProgress(i); }
System.Threading.Thread.Sleep(10); }
return -1; }
sender,
private void btnStart_Click(object sender, EventArgs e) {
worker.RunWorkerAsync(); btnStart.Enabled = false; btnPause.Enabled = true; }
private void btnPause_Click(object sender, EventArgs e) {
btnPause.Enabled = false; btnStart.Enabled = true; worker.CancelAsync(); } } }