Question

我想创建自动进度条，当我运行程序时会弹出...

我的程序有6个函数/ sub运行查询需要很长时间才能完成，关于input约为1-2分钟

我正在使用backgroundworker处理线程并将其与progressbar

组合

这是我的代码

的RunWorkerAsync

Private Sub ButtonX1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonX1.Click
    BackgroundWorker1.WorkerReportsProgress = True
    BackgroundWorker1.RunWorkerAsync()
End Sub

Do_work

Private Sub BackgroundWorker1_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork

    For i As Integer = 0 To 100000000
        create_tree()
        localtree()
        localfrek()
        create_combination()
        showresult()
        If i Mod 10000000 Then
            BackgroundWorker1.ReportProgress(i / 100)
        End If
    Next


End Sub

ProgressChanged

 Private Sub BackgroundWorker1_ProgressChanged(ByVal sender As Object, ByVal e As System.ComponentModel.ProgressChangedEventArgs) Handles BackgroundWorker1.ProgressChanged
    ProgressBar1.Visible = True
    ProgressBar1.Value = e.ProgressPercentage
End Sub

RunWorkerCompleted

Private Sub BackgroundWorker1_RunWorkerCompleted(ByVal sender As Object, ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles BackgroundWorker1.RunWorkerCompleted
    MessageBox.Show("Task completed!")
End Sub

问题是

the progress bar没有弹出
功能在完成前停止

第二个问题我认为是因为我在for loop事件中使用的Do_work

我不知道每个函数的经过时间，所以我在for loop中使用随机整数

Answer 1

首先，您应该在致电Visible之前设置ProgressBar的{{1}}属性。

其次，您应该将RunWorkerAsync与某些内容进行比较。

第三，如果i Mod 10000000达到10000000，则i将超过100。

vb net backgroundworker +进度条

1 个答案: