当我取消并处置我的后台工作人员时，尽管它从 VS 线程列表中消失了，但它继续向等待它关闭的我的应用程序报告忙。我的 RunWorkerCompleted 事件也永远不会引发。
调试显示代码已退出，我看不到进一步的挂起执行。
如果我删除 .IsBusy 检查，VS 会报告“此 BackgroundWorker 当前很忙，无法同时运行多个任务”
我不明白为什么 VS 中不再列出的线程在关闭后继续运行。
private void UpdateTimeLine()
{
txtb_timeline.Text = "Updating...";
startTimelineUpdater.DoWork += new DoWorkEventHandler(startTimelineUpdater_DoWork);
startTimelineUpdater.RunWorkerAsync("hometimeline");
startTimelineUpdater.WorkerReportsProgress = true;
startTimelineUpdater.ProgressChanged += new ProgressChangedEventHandler
(startTimelineUpdater_ProgressChanged);
startTimelineUpdater.WorkerSupportsCancellation = true;
}
void startTimelineUpdater_DoWork(object sender, DoWorkEventArgs e)
{
//begin the thread to maintain updates of SQL
beginRegUpdateTimeline.DoWork += new DoWorkEventHandler(beginRegUpdateTimeline_DoWork);
beginRegUpdateTimeline.RunWorkerAsync();
beginRegUpdateTimeline.WorkerSupportsCancellation = true;
while (true)
{
List<string[]> sqlset;
Xtweet getSQL = new Xtweet();
if(e.Argument.ToString() == "hometimeline")
{
sqlset = getSQL.CollectLocalTimelineSql();
}
else
{
sqlset = getSQL.CollectLocalTimelineSql(Int64.Parse(e.Argument.ToString()));
}
int i = 0;
while (i < 10)
{
foreach (var stringse in sqlset)
{
StringBuilder sb = new StringBuilder();
sb.Append(stringse[0]);
sb.Append(": ");
sb.Append(stringse[1]);
sb.Append(" @ ");
sb.Append(stringse[2]);
sb.Append("\n");
BackgroundWorker bkgwk = sender as BackgroundWorker;
bkgwk.ReportProgress(0, sb.ToString());
Thread.Sleep(1000);
i++;
if(startTimelineUpdater.CancellationPending)
{
e.Cancel = true;
startTimelineUpdater.Dispose();
break;
}
}
if (e.Cancel == true)
{
break;
}
}
if (e.Cancel == true)
{
break;
}
}
}
/// <summary>
/// Handles the DoWork event of the beginRegUpdateTimeline control.
/// Updates the timeline sql on a regular basis
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.ComponentModel.DoWorkEventArgs"/> instance containing the event data.</param>
void beginRegUpdateTimeline_DoWork(object sender, DoWorkEventArgs e)
{
while (true)
{
//update time in seconds
int secs = 10;
Xtweet.PreSqlDataCollection(null,null);
Thread.Sleep(secs*1000);
if(beginRegUpdateTimeline.CancellationPending)
{
e.Cancel = true;
beginRegUpdateTimeline.Dispose();
break;
}
}
}
private void startTimelineUpdater_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
txtb_timeline.Text = e.UserState.ToString();
}