新手求教，这段代码是什么意思
<%
if cstr(session("getcode"))<>cstr(Session("useryz")) then
response.codePage =65001
response.Charset="UTF-8"
response.Write "<script language='javascript'>"
response.Write "alert('验证码输入有误，请核对！');"
response.Write "history.go(-1);"
response.Write "</script>"
response.End
end if
%>
