| Nothing和字符串的VB.Net示例 |
| 作者：msdn 來源：microsoft 更新時間：2008-2-5 |
| 當(dāng)遇到字符串時，Visual Basic 運行庫和 .NET Framework 計算 Nothing 的方式有所不同。  請看下面的示例： Visual Basic  Dim MyString As String = "This is my string" Dim stringLength As Integer ' Explicitly set the string to Nothing. MyString = Nothing ' stringLength = 0 stringLength = Len(MyString) ' This line, however, causes an exception to be thrown. stringLength = MyString.Length Visual Basic 運行庫通常將 Nothing 作為空字符串 ("") 計算。但是 .NET Framework 則不同， 每當(dāng)嘗試對 Nothing 執(zhí)行字符串操作時都將引發(fā)異常。 |
