if ($pas1!=$pas2)
{
echo "<script language='javascript'>alert('两次密码不相同');history.go(-1);</script>";
exit;
}
$ar=mssql_fetch_array(mssql_query("SELECT COUNT(*) AS ID FROM per WHERE username = '".$username."'"));
if($ar[0]>0)
{
echo "<script language='javascript'>alert('用户名已经存在了');history.go(-1);</script>";
exit;
}
$ar=mssql_fetch_array(mssql_query("SELECT COUNT(*) AS ID FROM per WHERE email = '".$email."'"));
if($ar[0]>0)
{
echo "<script language='javascript'>alert('email已经存在了');history.go(-1);</script>";
exit;
}
exit必须要加吗？？？