php中的登陆login，php登陆login

<?<span>php 
</span><span>require</span> "../include/DBClass.php"<span>; 
</span><span>$username</span>=<span>$_POST</span>['UserName'<span>]; 
</span><span>$password</span>=<span>$_POST</span>['Password'<span>]; 
</span><span>if</span>(<span>empty</span>(<span>$username</span>) || <span>empty</span>(<span>$password</span><span>)){ 
  Go_Msg(</span>"请填写用户名，密码！","../default.html"<span>); 
  </span><span>exit</span><span>; 
 } 
DBConn(); 
</span><span>$password</span>=<span>md5</span>(<span>$password</span><span>); 
</span><span>$SQL</span> = "Select UserName,UserType,UserPass From siteuser where UserName='" . <span>$username</span> ."' and UserPass='" . <span>$password</span> . "' and isopen=1"<span>; 
</span><span>//</span><span>echo "$SQL"; </span>
<span>$result</span> = <span>$db</span> -> exec_SQL(<span>$SQL</span><span>); 
 </span><span>$total</span>=<span>mysql_num_rows</span>(<span>$result</span><span>); 
 </span><span>if</span>(<span>$total</span>==0<span>){ 
  DBClose(); 
  Go_Msg(</span>"注册用户还没有通过管理员审核或用户名及密码不符！请重新输入！","../default.html"<span>); 
  </span><span>exit</span><span>; 
 }</span><span>else</span><span>{ 
  </span><span>$Rs</span> = <span>$db</span> -> fetch_array(<span>$result</span><span>); 
  </span><span>//</span><span>附值，并登录 </span>
  <span>session_register</span>("username"<span>); 
  </span><span>session_register</span>("usertype"<span>); 
  </span><span>$_SESSION</span>["usertype"]=<span>$Rs</span>['UserType'<span>]; 
  </span><span>$_SESSION</span>["username"]=<span>$username</span><span>; 
  </span><span>//</span><span>echo $_SESSION["username"]; </span>
  <span>if</span> (<span>$_SESSION</span>["usertype"]==1<span>){ 
    Go_Msg(</span>"登陆成功！","default.php"<span>); 

    </span><span>//</span><span>header('Location:http://163.com'); </span>
<span>  } 
  </span><span>if</span> (<span>$_SESSION</span>["usertype"]==2<span>){ 
     Go_Msg(</span>"登陆成功！","../user2/default_1.php"<span>); 
  } 
  </span><span>if</span> (<span>$_SESSION</span>["usertype"]==3<span>){ 

     Go_Msg(</span>"登陆成功！","../user3/default_2.php"<span>); 
  } 
  </span><span>//</span><span> header('Location:default.php'); </span>
<span> } 
DBClose(); 
</span><span>//</span><span> 何问起 hovertree.com</span>
?>