如何找到 ContextMenuStrip 的发送者? [英] How can I find the sender of ContextMenuStrip?

问题描述

情况:

我有一个 VB.NET 形式的上下文菜单，在 ItemClicked 上触发事件处理程序.自动生成的子程序接收sender 和e 作为参数.由于我不会多次重新发明轮子，因此我将此上下文菜单链接到三个文本框.我们将它们命名为 Textbox1、Textbox2 和 Textbox3.

I have a context menu in a VB.NET form with fires an event handler on ItemClicked. The auto-generated subroutine receives sender and e as parameters. As I don't reinvent the wheel multiple times, I linked this context menu to three text boxes. Let's name them Textbox1, Textbox2 and Textbox3.

问题:如何确定菜单是在哪个文本框中打开的?

Problem: How can I figure out in which textbox the menu was opened?

好的，我已经尝试了什么?

Okay, what did I already try?

• sender 包含菜单本身，
• e.ClickedItem 只返回被选中的单个菜单项.
• sender.Parent 总是什么都没有
• sender.OwnerItem 也总是 Nothing`
• Me.Textbox1.Focused 总是 False，即使它是父"控制菜单.

• sender contains the menu itself,
• e.ClickedItem just returns the single menu item that was selected.
• sender.Parent is always nothing
• sender.OwnerItem is also always Nothing`
• Me.Textbox1.Focused is always False, even if its the "parent" control of the menu.

推荐答案

好的，我找到了一个可以正常工作的解决方案，这里是所有遇到相同问题的 VB.NET 编码人员的代码.

Okay, I found a solution that works fine, and here's the code for all VB.NET coders that have the same problem.

上下文菜单链接在TextBox1中，因此我们需要添加另一个事件处理程序，将发送控件保存到菜单中:

The context menu is linked in TextBox1, so we need to add another event handler that saves the sending control into the menu:

Private Sub TextBox1_MouseUp(sender As Windows.Forms.Control, e As System.Windows.Forms.MouseEventArgs) Handles TextBox1.MouseUp
    If e.Button = Windows.Forms.MouseButtons.Right Then
        ContextMenu.Tag = sender
    End If
End Sub

这是单击菜单项时事件处理程序的代码:

And this is the code of the event handler when clicking a menu item:

Private Sub ContextMenu_ItemClicked(sender As System.Object, e As System.Windows.Forms.ToolStripItemClickedEventArgs) Handles ContextMenu.ItemClicked
    ContextMenu.Close()

    If ContextMenu.Tag Is Nothing Then
        Debug.Print("debug info: forgot to set sender? well ... KABOOM!")
        Exit Sub
    End If

    Dim oParent As Windows.Forms.Control
    Try
        oParent = ContextMenu.Tag
    Catch ex As Exception
        Debug.Print("debug info: tag contains data other than sender control. well ... KABOOM!")
        Exit Sub
    End Try

    ' Do fancy stuff here.

    ' Release sender
    ContextMenu.Tag = Nothing
End Sub

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