c#异步操作,BackgroundWorker类的使用,可以在后台运行需要的代码逻辑。
namespace TestBackgroundWork
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
InitializeBackgoundWorker();
}
private BackgroundWorker backgroundWorker1;
private void InitializeBackgoundWorker()
{
this.backgroundWorker1 = new System.ComponentModel.BackgroundWorker();
this.backgroundWorker1.WorkerReportsProgress = true;
this.backgroundWorker1.WorkerSupportsCancellation = true;
this.backgroundWorker1.DoWork += new DoWorkEventHandler(backgroundWorker1_DoWork);
this.backgroundWorker1.ProgressChanged += new ProgressChangedEventHandler(backgroundWorker1_ProgressChanged);
this.backgroundWorker1.RunWorkerCompleted += new RunWorkerCompletedEventHandler(backgroundWorker1_RunWorkerCompleted);
}
//**********backgroundWorker1的回调函数**********
void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
BackgroundWorker worker = sender as BackgroundWorker;
for (int i = 1; i <= 10; i++)
{
if (worker.CancellationPending)
{
e.Cancel = true;
}
else
{
Thread.Sleep(500);
int percentComplete = (int)((float)i / (float)10 * 100);
worker.ReportProgress(percentComplete);
}
}
}
void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
this.progressBar1.Value = e.ProgressPercentage;
}
void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if (e.Error != null)
{
MessageBox.Show(e.Error.Message);
}
else if (e.Cancelled)
{
resultLabel.Text = "Canceled";
}
else
{
resultLabel.Text = "Completed";
}
startBtn.Enabled = true;
stopBtn.Enabled = false;
}
//**********backgroundWorker1的回调函数**********
private void startBtn_Click(object sender, EventArgs e)
{
resultLabel.Text = String.Empty;
this.startBtn.Enabled = false;
this.stopBtn.Enabled = true;
//启动异步操作.
backgroundWorker1.RunWorkerAsync();
}
private void stopBtn_Click(object sender, EventArgs e)
{
backgroundWorker1.CancelAsync();
}
}
}
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