BackgroundWorker,访问数据库查询的问题
前几天看了个大神的贴子，学习了用BackgroundWorker控件，在Dowork里做花时间长的处理。
正好的我的程序里有个地方，需要查询数据库，且执行这个SQL文需要花费很长的时间大约1分钟吧。为了在查询时不叫画面死掉，所以就用了BackgroundWorker。
代码如下。
Private Sub FrmReports_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load Me.BackgroundWorker1.WorkerReportsProgress = True Me.BackgroundWorker1.WorkerSupportsCancellation = TrueEnd Sub开始执行 Private Sub startAsyncButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles startAsyncButton.Click If BackgroundWorker1.IsBusy <> True Then BackgroundWorker1.RunWorkerAsync() End If End Sub取消按钮 Private Sub cancelAsyncButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cancelAsyncButton.Click If BackgroundWorker1.WorkerSupportsCancellation = True BackgroundWorker1.CancelAsync() End If End Sub查询 Private Sub BackgroundWorker1_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork Dim worker As BackgroundWorker = CType(sender, BackgroundWorker) Dim hashSearch As New Hashtable hashSearch.Item("AcceptDateF") = "2012-01-01 00:00:00" hashSearch.Item("AcceptDateT") = "2012-03-01 59:59:59" Dim dbCls As New DbInputData '这句话执行SQL问查询，费时1分钟，这个时候画面死掉了。。 dbRet = dbCls.SearchAcceptDataList(hashSearch, False, 50, 1) End Sub Private Sub BackgroundWorker1_ProgressChanged(ByVal sender As Object, ByVal e As System.ComponentModel.ProgressChangedEventArgs) Handles BackgroundWorker1.ProgressChanged 这啥也没写，本应该在这通过BackgroundWorker1.ReportProgress的方法来执行这个方法的 但是，DoWork中，没有能BackgroundWorker1.ReportProgress的地方了我觉的。。 End Sub完成方法 Private Sub BackgroundWorker1_RunWorkerCompleted(ByVal sender As Object, ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles BackgroundWorker1.RunWorkerCompleted If e.Cancelled = True Then resultLabel.Text = "Canceled!" ElseIf e.Error IsNot Nothing Then Else resultLabel.Text = "完成 " & dbRet.Count End If End Sub