VB.net 后台工作人员 UI

Question

我正在尝试创建一个可根据用户输入生成 excel 文档的应用程序。该文档可能会变得非常广泛（多张），所以我想将文档的创建放在 BackgroundWorker 上并将进度传递给 ProgressBar。

我在创建文档时访问 UI 控件时遇到问题。如何从 BackgroundWorker 访问多个 UI 控件？

这是我想在 BackgroundWorker 中做的许多事情中的两个非常基本的例子：

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

    Dim Combobox() As ComboBox = {ComboBox1, ComboBox2, ComboBox3, ComboBox4}

    With xlWorkBook.Sheets("Cover1")
        .Range("E5").Value = TextBox1.Text
        .Range("E6").Value = TextBox2.Text
        .Range("E7").Value = TextBox3.Text
        .Range("E8").Value = TextBox4.Text

        For i = 0 To Combobox.Count - 1
            .Range("A" & i + 1).Value = Combobox(i).Text
        Next
    End With

    CloseWorkBook()
End Sub

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

我完全没有经验，在研究了这个主题之后，我仍然无法与 Delegate/Invoke 相处。任何帮助都是极好的。提前致谢。

Answer 1

正如 Heinzi 所指出的，您不能只将对控件的引用传递到 bgw 中。相反，您传递值。

             Option Strict On
            Public Class FormControls
                WithEvents Bgw As New ComponentModel.BackgroundWorker With {.WorkerReportsProgress = True}

                Public Class BgwArgs
                    Public TxtBx1Txt As String = FormControls.TextBox1.Text
                    Public TxtBx2Txt As String = FormControls.TextBox2.Text
                    Public CmbBx1Txt As String = FormControls.ComboBox1.SelectedText
                End Class

                Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
                    Dim BgwArgs As New BgwArgs
                    Bgw.RunWorkerAsync(BgwArgs)
                End Sub

                Private Sub Bgw_DoWork(sender As Object, e As ComponentModel.DoWorkEventArgs) Handles Bgw.DoWork
                    Dim BgwArgs As BgwArgs = DirectCast(e.Argument, BgwArgs)

                    .Range("E5").Value = BgwArgs.TxtBx1Txt 'etc

                End Sub

            End Class

我假设 OpenWorkbook 是一个使用互操作来创建 xlWorkBook 的子程序，而您也想在线程内执行此操作，与 CloseWorkbook 一样，所有这些都应该是在 DoWork 事件中处理，而不是在它们自己的单独例程中处理。

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