關於VB.NET的委託

 

委託可以認爲是一類方法簽名一致的方法抽象類。

委託對象必須由簽名一致的方法實例化，而通過調用委託對象可以調用實例化委託對象的方法。

 

 

Public Class Form1
    Public Delegate Function addMethod(ByVal x, ByVal y) As Integer

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

        Dim a As addMethod
        Dim b As Tdelegate

        b = New Tdelegate()
        a = New addMethod(AddressOf b.add)

        'TextBox1.Text = TextBox1.Text + a(3, 9).ToString
        'TextBox1.Text = TextBox1.Text + (New addMethod(AddressOf New Tdelegate().add))(3, 9).ToString
        TextBox1.Text = TextBox1.Text + New addMethod(AddressOf New Tdelegate().add).Invoke(3, 9).ToString

    End Sub
End Class

Public Class Tdelegate

    Public Function add(ByVal x, ByVal y) As Integer

        Return x + y

    End Function

End Class