Question

我正在尝试将自己的参数（ Index As Integer 而不是 sender As Object，e As EventArgs ）发送到AddHandler。这是我的代码：

Dim Button_ as Button
For Index=0 To 9
    Button_ = New Button()
    Button_.Left = 10
    Button_.Top = (Index * 30) + 10
    Button_.Width = 100
    Button_.Height = 20
    AddHandler Button_.Click, AddressOf Button_Click(Index)
    Me.Controls.Add(Button_)
Next

Sub Button_Click(Index As Integer)
    'Do stuff here...
End Sub

由于

Answer 1

你不能改变Click事件处理程序的签名，但如果你指定了它的名字（我假设它是一个WinForm按钮），你可以检测点击了哪个按钮。

Dim Button_ as Button
For Index=0 To 9
    Button_ = New Button()
    Button_.Left = 10
    Button_.Top = (Index * 30) + 10
    Button_.Width = 100
    Button_.Height = 20

    Button_.Name = "Button_" & Index.ToString()

    AddHandler Button_.Click, AddressOf Button_Click
    Me.Controls.Add(Button_)
Next

然后您可以使用这样的标准签名：

Sub Button_Click(sender As Object, e As EventArgs)
     Dim Button_ as Button = CType(sender, Button)
     Dim ButtonName = Button.Name
End Sub

如果需要，您可以从名称派生实际索引。

Dim Index as Integer = CInt(ButtonName.Substring(7))

Answer 2

除了其他答案外，您的按钮还有一个名为Tag的属性，它被定义为一个对象。当我需要使用带有控制数组的公共事件处理程序时，我通常会使用此属性，你会使用类似的东西。

Dim Button_ as Button
For Index=0 To 9
    Button_ = New Button()
    Button_.Left = 10
    Button_.Top = (Index * 30) + 10
    Button_.Width = 100
    Button_.Height = 20
    Button_.Tag = Index
    AddHandler Button_.Click, AddressOf Button_Click
    Me.Controls.Add(Button_)
Next

Private Sub Button_Click(sender As Object, e As EventArgs)
    Dim i As Integer = CInt((CType(sender, Button).Tag))
    ' Use your index accordingly
End Sub

如何将我自己的参数发送到AddHandler

2 个答案: