Question

我正在尝试登录/注册页面。但是我在注册页面遇到了问题。这是我的代码：

<?php
error_reporting(0);
session_start();


 if (isset($_REQUEST['register']))
 {
 $username = $_REQUEST['user'];
 $pass = $_REQUEST['pass'];

 if ($username=="")
 {
     die("<br /> You Forgot to type in the Username for the user !<br><br>Redirecting back to the previous page...<meta HTTP-EQUIV='Refresh' CONTENT='3; URL=signup.php'> ");
 }
 if ($pass=="")
 {
     die("<br /> You Forgot to type in the Password for the user !<br><br>Redirecting back to the previous page...<meta HTTP-EQUIV='Refresh' CONTENT='3; URL=signup.php'> ");
 }

 $connect = mysql_connect("localhost", "root", "");
 if(!$connect)
 {
     die(mysql_error());
 }

 $select_db = mysql_select_db("new");
 if(!$select_db)
 {
     die(mysql_error());
 }

 mysql_query("INSERT INTO users (username, password) 
              VALUES ('$username', '$pass') ");
 } 

 ?>

我想限制用户名，就像用户名已经存在一样。使用此代码，可以有很多具有相同用户名的注册。所以我想对此加以限制。

Answer 1

$sqlstr = "SELECT username FROM users WHERE username = '$username'";
if (!$res = $connect->query($sqlstr)) {
    trigger_error('Error in query ' . $connect->error);
} else {
    if ($res->num_rows == 0) {
       //username does not exist yet
    } else {
       //username exists already
    }
}

这将检查您的数据库中的给定用户

在制作注册页面时需要帮助

1 个答案: