Question

我将使用property来保存click sub的地址，然后将其分配给AddRow（）子句中的每个按钮。出现以下错误时出现问题：

错误1

方法'公共属性ClickEvent As Button_Click'没有签名与委托'Delegate Sub EventHandler（发件人）兼容 As Object，e As System.EventArgs）'。

Private Sub Button_Click(sender As Object, e As EventArgs)
    'do somthing
End Sub

Class CustomClass
    Public Fields As New List(Of FieldsDefinition)()

    Class FieldsDefinition
        Public Delegate Sub Button_Click(sender As System.Object, e As System.EventArgs)

        Public __ClickEventValue As Button_Click
        Public Property ClickEvent() As Button_Click
            Get
                Return __ClickEventValue
            End Get

            Set(ByVal value As Button_Click)
                __ClickEventValue = value
            End Set
        End Property
    End Class

    Public Sub AddRow()
        For Each field As FieldsDefinition In Fields
            Dim ctrl As New TextBox
            AddHandler ctrl.Click, AddressOf field.ClickEvent
        Next
    End Sub
End Class

Answer 1

2个变化：

删除AddressOf，因为您不希望处理程序成为ClickEvent属性本身，您希望它是返回的委托。
AddHandler会期望类型为EventHandler的处理程序。因此，请删除Button_Click委托声明，并用EventHandler替换对它的任何引用。

代码：

Private Sub Button_Click(sender As Object, e As EventArgs)
    'do somthing
End Sub

Class CustomClass
    Public Fields As New List(Of FieldsDefinition)()

    Class FieldsDefinition
        ' removed Button_Click delegate declaration here

        Public __ClickEventValue As EventHandler 'changed Button_Click to EventHandler here
        Public Property ClickEvent() As EventHandler 'changed Button_Click to EventHandler here
            Get
                Return __ClickEventValue
            End Get

            Set(ByVal value As EventHandler) 'changed Button_Click to EventHandler here
                __ClickEventValue = value
            End Set
        End Property
    End Class

    Public Sub AddRow()
        For Each field As FieldsDefinition In Fields
            Dim ctrl As New TextBox
            AddHandler ctrl.Click, field.ClickEvent 'removed AddressOf here
        Next
    End Sub
End Class

保留sub属性的地址

1 个答案: