asp 字元處理常式

<%
'*************************************************
'函數名：gotTopic
'作  用：截字串，漢字一個算兩個字元，英文算一個字元
'參  數：str   ----原字串
'       strlen ----截取長度
'傳回值：截取後的字串
'*************************************************
function gotTopic(str,strlen)
 if str="" then
  gotTopic=""
  exit function
 end if
 dim l,t,c, i
 str=replace(replace(replace(replace(str,"&nbsp;"," "),"&quot;",chr(34)),"&gt;",">"),"&lt;","<")
 l=len(str)
 t=0
 for i=1 to l
  c=Abs(Asc(Mid(str,i,1)))
  if c>255 then
   t=t+2
  else
   t=t+1
  end if
  if t>=strlen then
   gotTopic=left(str,i) & "…"
   exit for
  else
   gotTopic=str
  end if
 next
 gotTopic=replace(replace(replace(replace(gotTopic," ","&nbsp;"),chr(34),"&quot;"),">","&gt;"),"<","&lt;")
end function