.net 如何通过DragandDrop只知道接口传递对象？

有很多东西 实现一个接口 如何在只知道用户界面的情况下通过DragandDrop传递对象

Public Class test_1
    Implements I_NAME
    Public Property Name As String Implements I_NAME.Name
End Class

Public Class WPF_TEST

Private Sub txt_drop_source_MouseDown(sender As Object, e As MouseButtonEventArgs) Handles      txt_drop_source.MouseDown
    Dim obj As New test_1
    DragDrop.DoDragDrop(Me, obj, DragDropEffects.All)
End Sub

Private Sub txt_drop_DragEnter(sender As Object, e As DragEventArgs) Handles txt_drop.DragEnter
    If e.Data.GetDataPresent(GetType(I_NAME)) Then
        e.Effects = DragDropEffects.All
    End If
End Sub

Private Sub txt_drop_Drop(sender As Object, e As DragEventArgs) Handles txt_drop.Drop
    Dim obj As Object = e.Data.GetData(GetType(I_NAME))
    If IsNothing(obj) = False Then
        MsgBox(obj.ToString)
    End If
End Sub

End Class

此处不能使用GetDataPresent（），因为您不知道类的名称。因此，实际调用GetData（）并使用is运算符查看它是否实现了接口