ASP查询无限级分类子栏目ID

我写了一个查询无限级子栏目ID的函数，代码如下：
Function ChildSort(Cuz,SortID)
fSortID = Int(SortID)
Set RsLs=server.CreateObject("adodb.recordset")
Sql="Select SortID From [Cuz_"&Cuz&"Sort] where ParentID="&fSortID&" order by SortSeq"
RsLs.Open Sql,Conn,1,1
While Not RsLs.Eof
ChildSort=ChildSort&","&Int(RsLs("SortID"))&ChildSort(Cuz,RsLs("SortID"))
RsLs.MoveNext
Wend

RsLs.Close:Set RsLs=Nothing
End Function
显示结果是“，1，2，3”的形式，如何在函数内把最前面的“，”去掉，注意我说的函数内解决

if ChildSort ="" or isnull(ChildSort)
then ChildSort=&Int(RsLs("SortID"))&ChildSort(Cuz,RsLs("SortID"))
else
ChildSort=ChildSort&","&Int(RsLs("SortID"))&ChildSort(Cuz,RsLs("SortID"))
end if