ASP判断来访者从哪个搜索引擎访问

function GetSearcher() 
Dim botlist,Searcher 
Dim vibo_soft 
vibo_soft=Request.ServerVariables("HTTP_USER_AGENT") 

Botlist="Google,Isaac,SurveyBot,Baiduspider,ia_archiver,P.Arthur,FAST-WebCrawler,Java,Microsoft-ATL-Native,TurnitinBot,WebGather,Sleipnir,TencentTraveler" 
Botlist=split(Botlist,",") 
  For i=0 to UBound(Botlist) 
    If InStr(vibo_soft,Botlist(i))>0  Then  
      Searcher=Botlist(i)&" 搜索器" 
      IsSearch=True 
      Exit For 
    End If 
  Next  
If IsSearch Then  
  GetSearcher=Searcher 
else 
  GetSearcher="unknown" 
End if 
End function