[VB6 ] 判斷Picture物件是否有圖片
在書上，
判斷Picture圖片是否含有物件的函式是這樣寫的：
Function HasPicture(pic As Picture) As Boolean
If pic Is Nothing Then
HasPicture = False
ElseIf pic.Handle = 0 Then
HasPicture = False
Else
HasPicture = True
End If
End Function
但是我有個問題，
為什麼要分別對pic.Handle、pic Is Nothing做兩次判斷？
難道當pic=Nothing之後，pic.handle還會存在嗎？
不能直接判斷pic Is Nothing或是pic.handle的其中一個就可以嗎？
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