asp 字符处理程序

<%
'*************************************************
'函数名：gotTopic
'作  用：截字符串，汉字一个算两个字符，英文算一个字符
'参  数：str   ----原字符串
'       strlen ----截取长度
'返回值：截取后的字符串
'*************************************************
function gotTopic(str,strlen)
 if str="" then
  gotTopic=""
  exit function
 end if
 dim l,t,c, i
 str=replace(replace(replace(replace(str," "," "),""",chr(34)),">",">"),"<","<")
 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," "," "),chr(34),"""),">",">"),"<","<")
end function