在进行数据库的查询时，会经常遇到这样的情况：
　　例如想在一个用户数据库中查询他的用户名和他的密码，但恰好该用户使用的名字和密码中有特殊的字符，例如单引号，“|”号

双引号或者连字符“&”。

　　例如他的名字是1'test，密码是A|&900

这时当你执行以下的查询语句时，肯定会报错：

SQL = "SELECT * FROM SecurityLevel WHERE UID='" & UserID & "'"

SQL = SQL & " AND PWD='" & Password & "'"

因为你的SQL将会是这样：

SELECT * FROM SecurityLevel WHERE UID='1'test'

AND PWD='A|&900'

在SQL中，"|"为分割字段用的，显然会出错了。现在提供下面的几个函数 专门用来处理这些头疼的东西：

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

有了上面几个函数后，当你在执行一个sql前，请先使用

SQL = "SELECT * FROM SecurityLevel WHERE UID='" & SQLFixup(UserID) & "'"

SQL = SQL & " AND PWD='" & SQLFixup(Password) & "'"