帮忙看一小段代码 问题！！！！
Identification()

'传入参数
Dim ClassName, cPage, cUrl, tTypeID, cType, wSql
Dim sID, sTitle, sNum

ClassName = SafeRequest("Action",0)

tTypeID = SafeRequest("TypeID",1)
If tTypeID <> "" Then
cType = "?TypeID=" & cType
wSql = "n.nType = "& tTypeID &" AND"
End If

cPage = SafeRequest("Page",1)
If cPage = "" Then
cUrl = "Diagramtext.Asp" & cType
Else
If cType <> "" Then
cUrl = "Diagramtext.Asp"& cType &"&Page=" & cPage
Else
cUrl = "Diagramtext.Asp?Page=" & cPage
End If
End If

Select case ClassName
case "cTop"
cInfocTop
case "Del"
cInfoDel
case "GoPage"
Response.Redirect("Diagramtext.Asp?Page=" & Request.Form("PageKey"))
End Select
%>

这段代码 哪里能看出TypeID后面为空

[解决办法]
If tTypeID <> "" Then
cType = "?TypeID=" & cType
wSql = "n.nType = "& tTypeID &" AND"
End If