使用 'AddressOf' 添加处理程序

Question

尝试向动态创建的按钮添加事件处理程序时出现错误：

Dim Itm As New Button
Itm.Name = "Itm" & i
Itm.Height = 62
Itm.Width = 159
Itm.Text = Temp(i, 0).ToUpper
Itm.Left = (F * 165)
Itm.Visible = True
Itm.BackColor = Colour
Itm.ForeColor = Color.Black
AddHandler Itm.Click, AddressOf Me.Itm_Click
Me.pnlItemButton1.Controls.Add(Itm)
i = i + 1
If i > Temp.Length - 1 Then
    GoTo Exit1
End If

我在 AddressOf 行收到一个错误：

"Item_Click is not a member of windowsapplication1.main"

我觉得这是因为我将名称设置为 "Itm" & i 但使用 AddressOf Me.Itm(i)_Click 也会出现错误。有什么想法吗？

Answer 1

您必须声明 event handler Itm_Click 并且它必须是可访问的。

例如（假设您的数组 Temp 存在于某处）：

Public Class Demo
    Protected Sub Itm_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) 

    End Sub

    Public Sub DemoMethod()
        For i As Int32 = 1 To Temp.Length - 1
            Dim Itm As New System.Windows.Forms.Button()
            Itm.Name = "Itm" & i
            Itm.Height = 62
            Itm.Width = 159
            Itm.Text = Temp(i, 0).ToUpper
            Itm.Left = (F * 165)
            Itm.Visible = True
            Itm.BackColor = Colour.White
            Itm.ForeColor = Color.Black
            AddHandler Itm.Click, AddressOf Me.Itm_Click
            Me.pnlItemButton1.Controls.Add(Itm)
        Next
    End Sub
End Class

您可以将此事件处理程序用于所有动态创建的按钮。您从 sender 参数中获得被点击的按钮：

Protected Sub Itm_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) 
    Dim actualButton = Ctype(sender, System.Windows.Forms.Button)
    Dim name = actualButton.Name
End Sub

使用 'AddressOf' 添加处理程序

Adding Handler using 'AddressOf'

vb.net

dynamic

button

handler

addressof