如何删除从控件集

Question

我有以下错误消息

  

＆＃39; AddressOf＆＃39;操作数必须是方法的名称（没有括号）

尝试以下代码时：

Private Sub Button1_Click(ByVal sender As System.Object, 
                          ByVal e As System.EventArgs) Handles Button1.Click
    Dim xbutton As Control

    For Each xbutton In gcFRightMenu.Controls
        If xbutton.Name = commandbutton(0) Then

            RemoveHandler xbutton.MouseDown, AddressOf xbutton.MouseDown

            AddHandler xbutton.MouseDown, AddressOf _MouseDown

        End If
    Next
End Sub


Private Sub _MouseDown(ByVal sender As Object, 
                       ByVal e As System.Windows.Forms.MouseEventArgs)
    If e.Button = Windows.Forms.MouseButtons.Left Then SendKeys.Send("{ESC}")
End Sub

Answer 1

您无法删除活动

RemoveHandler xbutton.MouseDown, AddressOf xbutton.MouseDown

AddressOf期待该方法的名称，但xbutton.MouseDown是事件的名称。

如果您想确保eventhandler _MouseDown仅向控件添加了一个，则在添加

之前始终将其删除

For Each xbutton In gcFRightMenu.Controls
    If xbutton.Name = commandbutton(0) Then

        RemoveHandler xbutton.MouseDown, AddressOf _MouseDown

        AddHandler xbutton.MouseDown, AddressOf _MouseDown

    End If
Next