抽象類別一問

看板C_Sharp (C#)作者liunate (測試)時間20年前 (2005/05/26 21:13)推噓2(2推 0噓 3→)

留言5則, 3人參與討論串1/1

我看過MISOO放在網站上關於抽象類別的教學，在活用抽象類別最後提到抽象類別還具有提供預設程序的功用，同時用下面的程式來展示。 Person是基礎結構的抽象類別，Customer inherits Person, VIP inherits Customer 根據教學文件中的輸出結果會有 Customer: Mr. White TEL: 888-2222 但是我看VIP類別有override Customer類別的Display() 怎麼還會使用到Customer.Disp ay()的內容呢? 預設程序不是要在子類別無override父類別的程序，這樣的情況下才成立嗎? 還請各位解惑了 (．＿．?) Class Person Protected name As String Public Sub New(ByVal na As String) name = na End Sub Public Overridable Sub Display() End Sub End Class Class Customer Inherits Person Public Sub New(ByVal na As String) MyBase.New(na) End Sub Public Overrides Sub Display() MessageBox.Show("Customer: " + name) End Sub End Class '------------------------------------------------------------------------------- Class VIP Inherits Customer Private tel As String Public Sub Newe(ByVal na As String, ByVal t As String) MyBase.New(na) tel = t End Sub Public Overrides Sub Display() MessageBox.Show("TEL: " + tel) End Sub End Class Protected Sub Form1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Dim v As New VIP("Mr. White", "8888-2222") v.Display() End Sub -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 211.74.98.216