Question

我有一个位于MDI父表单内的自定义选项卡控件。我在选项卡上有一个关闭按钮。单击选项卡关闭按钮时，将删除该选项卡，并删除MDI父窗体的相应MDI子窗体。在MDI子窗体上，我检查其FormClosing事件中的各种条件。如果不满足条件，则通过放置

取消表格的关闭

e.Cancel = True

在FormClosing事件中。这一切都有效，但是，当取消表单关闭时，我的选项卡已被删除，我不再有MDI子窗体的相应选项卡。如何从MDI子窗体的FormClosing事件返回Cancel，返回到MDI父窗体上的选项卡控件按钮的关闭事件？

我应该提到选项卡控件不是标准的.net选项卡，它是在标准的.net选项卡控件之上构建的，以允许选项卡上的关闭按钮。我没有为这个自定义选项卡控件编写原始代码。

以下是自定义标签控件＆＃39; TabControlEx＆＃39;的类中存在的标签关闭代码。

Public Event CloseButtonClick As CancelEventHandler
Protected Overridable Sub OnCloseButtonClick(ByVal sender As Object, ByVal e As EventArgs)
    If Not DesignMode Then
        Dim btn As Button = DirectCast(sender, Button)
        Dim tp As TabPage = CloseButtonCollection(btn)
        Dim ee As New CancelEventArgs
        RaiseEvent CloseButtonClick(sender, ee)
        If Not ee.Cancel Then
            Me.TabPages.Remove(tp)
            RePositionCloseButtons()
            Me.SelectedIndex = Me.TabCount - 1
        End If
    End If
End Sub

这是我在MDI父表单上的选项卡控件上使用的代码

Private Sub TabControl_CloseButtonClick(sender As Object, e As System.ComponentModel.CancelEventArgs) Handles TabControl.CloseButtonClick

    Dim i As Integer
    If TabControl.TabPages.Count > 0 Then
        For i = 0 To Me.MdiChildren.Length - 1
            If i = TabControl.SelectedIndex Then
                Me.MdiChildren(i).Close()
            End If
        Next
    End If

End Sub

这是MDI子窗体上存在的FormClosing代码。我简化了它以显示这种情况

Private Sub frmMyMdiChildForm_FormClosing(sender As Object, e As FormClosingEventArgs) Handles MyBase.FormClosing

    If (MsgBox("Do you wan to contiue closing", vbYesNo) = vbNo) Then
        e.Cancel = True
        'This is where I need to send the cancel command back to the sender somehow
        Exit Sub
    End If
End Sub

返回取消发件人VB.NET

0 个答案: