在進行數(shù)據(jù)庫的查詢時，會經(jīng)常遇到這樣的情況：
例如想在一個用戶數(shù)據(jù)庫中查詢他的用戶名和他的密碼，
但恰好該用戶使用的名字和密碼中有特殊的字符，例如單引號，“ ”號
雙引號或者連字符“&”
例如他的名字是1'test，密碼是A &900
這時當(dāng)你執(zhí)行以下的查詢語句時，肯定會抱錯：
SQL = "SELECT * FROM SecurityLevel WHERE UID='" & UserID & "'"
SQL = SQL & " AND PWD='" & Password & "'"
因為你的SQL將會是這樣：
SELECT * FROM SecurityLevel WHERE UID='1'test'
AND PWD='A &900'
在SQL中，" "為分割字段用的，顯然會出錯了。現(xiàn)在提供下面的幾個函數(shù)
專門用來處理這些頭疼的東西：

Function ReplaceStr (TextIn, ByVal SearchStr As String, _
ByVal Replacement As String, _
ByVal CompMode As Integer)
Dim WorkText As String, Pointer As Integer
If IsNull(TextIn) Then
ReplaceStr = Null
Else
WorkText = TextIn
Pointer = InStr(1, WorkText, SearchStr, CompMode)
Do While Pointer > 0
WorkText = Left(WorkText, Pointer - 1) & Replacement & _
Mid(WorkText, Pointer + Len(SearchStr))
Pointer = InStr(Pointer + Len(Replacement), WorkText, _
SearchStr, CompMode)
Loop
ReplaceStr = WorkText
End If
End Function

Function SQLFixup(TextIn)
SQLFixup = ReplaceStr(TextIn, "'", "''", 0)
End Function

Function JetSQLFixup(TextIn)
Dim Temp
Temp = ReplaceStr(TextIn, "'", "''", 0)
JetSQLFixup = ReplaceStr(Temp, " ", "' & chr(124) & '", 0)
End Function

Function FindFirstFixup(TextIn)
Dim Temp
Temp = ReplaceStr(TextIn, "'", "' & chr(39) & '", 0)
FindFirstFixup = ReplaceStr(Temp, " ", "' & chr(124) & '", 0)
End Function

有了上面幾個函數(shù)后，當(dāng)你在執(zhí)行一個sql前，請先使用
SQL = "SELECT * FROM SecurityLevel WHERE UID='" & SQLFixup(UserID) & "'"
SQL = SQL & " AND PWD='" & SQLFixup(Password) & "'" （出處：熱點網(wǎng)絡(luò)）