与多个控件交互的子事件

Question

我想调用这个代码片段，传递一个类似于参数的“control want”，然后sub与所需的控件交互。

我怎么能做到这一点？

这是代码片段：

#Region " Move a control in real-time "
    ' Change Textbox1 to the desired control name
    Private Sub TextBox1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles textbox1.MouseDown
        If e.Button = Windows.Forms.MouseButtons.Left Then
            textbox1.Capture = False
            Dim ControlMoveMSG As Message = Message.Create(textbox1.Handle, &HA1, New IntPtr(2), IntPtr.Zero)
            Me.DefWndProc(ControlMoveMSG)
        End If
    End Sub
#End Region

更新:解决方案：

Private Sub MoveControl(sender As Object, e As EventArgs) Handles _
        TextBox1.MouseDown, _
        TextBox2.MouseDown, _
        PictureBox1.MouseDown

    Dim control As Control = CType(sender, Control)
    control.Capture = False
    Dim ControlMoveMSG As Message = Message.Create(control.Handle, &HA1, New IntPtr(2), IntPtr.Zero)
    Me.DefWndProc(ControlMoveMSG)
End Sub

Answer 1

在这种情况下，您可以只使用sender。sender参数是对引发事件的任何控件的引用。因此，如果您将此相同的方法添加为多个控件的事件处理程序，则sender将是哪个控件引发了它当前正在处理的事件，例如：

Private Sub MouseDown(sender As Object, e As EventArgs) _
        Handles TextBox1.MouseDown, TextBox2.MouseDown
    ' Note in the line above that this method handles the event 
    ' for TextBox1 and TextBox2
    Dim textBox As TextBox = CType(sender, TextBox)
    ' textBox will now be either TextBox1 or TextBox2, accordingly
    textBox.Capture = False
    ' ....
End Sub

CType语句将基本Object参数强制转换为特定的TextBox类。在本例中，该方法只处理TextBox对象的事件，因此这是可行的。但是，如果让它处理来自其他类型控件的事件，则需要强制转换为更通用的Control类型(即CType(sender, Control))。