如何使用 VB Application.DoEvent？

我有一个进程在针对小文件运行时运行良好，但给出了“Message=Managed Debugging Assistant 'ContextSwitchDeadlock'：'CLR 无法从 COM 上下文 0xa5b8e0 转换到 COM 上下文 0xa5b828 60 秒”。针对大文件运行时出错。我对 VB 很陌生，做了一些调查，发现似乎建议使用 Application.DoEvent 。我希望有人可以向我展示如何使用它的示例。如果我正在执行一个名为“Process1”的子程序，我将如何使用 DoEvent 来防止它超时。理想情况下，我也想添加一个进度条，但我也不知道。我将不胜感激任何帮助。请保持简单，因为我是 VB/VS 的新手。

这是我显示代码的第一个问题的评论。 Process1 调用一个名为 ArchDtlCopyFile1 的子程序，该子程序滚动浏览列表视图中的值，将项目中指定的文件复制到不同的位置。然后，它调用 ArchDtlCheckCopy1 再次滚动列表视图以确保复制已完成。然后，它决定是否应删除源文件并根据需要执行删除操作。最后，它在 Access 表中插入一行记录所做的更改。

Private Sub Process1()
    If ReturnCode = 0 Then
        ArchDtlCopyFile1()
    Else
        ' MessageBox.Show("Error code coming in is: " & CStr(ReturnCode))
    End If

    If ReturnCode = 0 Then
        ArchDtlCheckCopy1()
    Else
        '  MessageBox.Show("Error code for check copy is: " & CStr(ReturnCode))
    End If
End Sub

Private Sub ArchDtlCopyFile1()

    intLVIndex = 0

    ' Copy the file from the source computer onto the NAS
    Do While intLVIndex < intMaxFileIndex
        Try

            ' Select the row from the LVFiles ListView, then move the first column (0) into strSourceFilePath and the last
            ' column (3) into strDestFilePath. Execute the CopyFile method to copy the file.
            LVFiles.Items(intLVIndex).Selected = True
            strSourceFilePath = LVFiles.SelectedItems(intLVIndex).SubItems(0).Text
            strDestFilePath = LVFiles.SelectedItems(intLVIndex).SubItems(3).Text
            My.Computer.FileSystem.CopyFile(strSourceFilePath, strDestFilePath, overwrite:=False)

        Catch ex As Exception

            ' Even if there's an error with one file, we should continue trying to process the rest of the files
            Continue Do

        End Try

        intLVIndex += 1

    Loop

End Sub

Private Sub ArchDtlCheckCopy1()

    intLVIndex = 0
    intLVError = 0

    '    ' Check each file was copied onto the NAS
    Do While intLVIndex < intMaxFileIndex


        ' Select the row from the LVFiles ListView, then move the last column (3) into strDestFilePath.
        ' Use the FileExists method to ensure the file was created on the NAS. If it was, call the
        ' ADetDelete Sub to delete the source file from the user's computer.

        LVFiles.Items(intLVIndex).Selected = True
        strSourceFilePath = LVFiles.SelectedItems(intLVIndex).SubItems(0).Text
        strDestFilePath = LVFiles.SelectedItems(intLVIndex).SubItems(3).Text
        strSourceFile = LVFiles.SelectedItems(intLVIndex).SubItems(1).Text
        Try

            If My.Computer.FileSystem.FileExists(strDestFilePath) Then
                ' Archive file was created so go ahead and delete the source file
                'If strSourceFile = myCheckFile Then
                '    strDestFile = LVFiles.SelectedItems(intLVIndex).SubItems(3).Text
                'End If
                If RBArchive.Checked = True Then
                    ArchDtlDeleteFile(strSourceFilePath)
                End If
                PrepareDtlVariables()
                ADtlAddRow()

            Else
                MessageBox.Show("File not found. " & strDestFilePath)
            End If

        Catch ex As Exception

            ErrorCode = "ARC6"
            MessageCode = "Error while checking file copy"
            ReturnCode = 8

        End Try

        intLVIndex += 1
    Loop

End Sub

这是一个简化的示例：

Imports System.ComponentModel
Imports System.IO
Public Class Form1

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        BackgroundWorker1.WorkerReportsProgress = True
    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Button1.Enabled = False
        BackgroundWorker1.RunWorkerAsync()
    End Sub

    Private Sub BackgroundWorker1_DoWork(sender As Object, e As DoWorkEventArgs) Handles BackgroundWorker1.DoWork
        For i As Integer = 1 To 20
            BackgroundWorker1.ReportProgress(i) ' you can pass anything out using the other overloaded ReportProgress()
            System.Threading.Thread.Sleep(1000)
        Next
    End Sub

    Private Sub BackgroundWorker1_ProgressChanged(sender As Object, e As ProgressChangedEventArgs) Handles BackgroundWorker1.ProgressChanged
        ' you can also use e.UserState to pass out ANYTHING
        Label1.Text = e.ProgressPercentage
    End Sub

    Private Sub BackgroundWorker1_RunWorkerCompleted(sender As Object, e As RunWorkerCompletedEventArgs) Handles BackgroundWorker1.RunWorkerCompleted
        MessageBox.Show("Done!")
        Button1.Enabled = True
    End Sub

End Class