The application of ASP to implement the method of heavy coding for SQL injection dangerous characters

<%
'******************************
' Function: Checkstr (byVal chkstr)
' Parameters: Chkstr, characters to be validated
' Author: Arisisi
' Date: 2007/7/15
' Description: SQL injection of dangerous characters for heavy-coded processing
' Example: Checkstr ("and 1=1 or select * from")
'******************************
Function checkstr (ByVal chkstr)
Dim Str:str=chkstr
Str=trim (STR)
If IsNull (STR) Then
Checkstr = ""
Exit Function
End If
Dim RE
Set re=new REGEXP
Re. IgnoreCase =true
Re. Global=true
Re. Pattern= "(\ r \ n) {3,}"
Str=re. Replace (STR, "$1$1$1")
Set re=nothing
str = Replace (str, "'", "" ")
str = Replace (str, "select", "select")
str = Replace (str, "join", "join")
str = Replace (str, "union", "union")
str = Replace (str, "where", "where")
str = Replace (str, INSERT, insert)
str = Replace (str, "delete", "delete")
str = Replace (str, "Update", "Update")
str = Replace (str, "like", "like")
str = Replace (str, "Drop", "drop")
str = Replace (str, "create", "create")
str = Replace (str, "Modify", "modify")
str = Replace (str, "rename", "Rename")
str = Replace (str, "ALTER", "alter")
str = Replace (str, "cast", "cast")
Checkstr=str
End Function

' Reverse the string processed by the above function

Function Uncheckstr (STR)
str = Replace (str, "select", "select")
str = Replace (str, "join", "join")
str = Replace (str, "union", "union")
str = Replace (str, "where", "where")
str = Replace (str, INSERT, insert)
str = Replace (str, "delete", "delete")
str = Replace (str, "Update", "Update")
str = Replace (str, "like", "like")
str = Replace (str, "Drop", "drop")
str = Replace (str, "create", "create")
str = Replace (str, "Modify", "modify")
str = Replace (str, "rename", "Rename")
str = Replace (str, "ALTER", "alter")
str = Replace (str, "cast", "cast")
Uncheckstr=str
End Function
%>