if instr(1,strContent,"[/rndtxt]",1)>0 then
        re.Pattern="(\[rndtxt\])(.[^\[]*)(\[\/rndtxt\])"
        myarray=split("$2","|")
        strContent=re.Replace(strContent,myarray(int(rnd()*ubound)+1))
    end if

Randomize 

s="~[rndtxt]内容1|内容2|内容3[/rndtxt]~afefefe~[rndtxt]内容4|内容5|内容6[/rndtxt]~[rndtxt]内容1|内容2|内容3[/rndtxt]"
set rx=new regexp
rx.ignorecase=true
rx.global=true
rx.pattern="\[rndtxt\]([\s\S]+?)\[/rndtxt\]"
set mc=rx.execute(s)
for each m in mc
  arr=split(m.submatches(0),"|")
  s=replace(s,m.value,arr(int(rnd()*ubound(arr))),1,1)'正则替换没有只执行一次的替换，所以改为replace方法
next

set rx=nothing

response.write s