委托可以认为是一类方法签名一致的方法抽象类。

委托对象必须由签名一致的方法实例化，而通过调用委托对象可以调用实例化委托对象的方法。

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