Question

注册表单通过db.php连接到数据库，但我在提交登录详细信息时遇到问题。

<html>
<head>
 <?php
 include('db.php');

$username = @$_POST['username'];
$password = @$_POST['password'];
$submit = @$_POST['submit'];

主要问题是在现有用户点击提交按钮后，它应该给出消息，但 if 语句中存在问题，因为在 wamp服务器< / b>仅显示 else 消息，即错误。

if ($submit) { $result = mysql_query("SELECT * FROM users WHERE username='$username' AND password='$password'"); if (mysql_num_rows($result)) { $check_rows = mysql_fetch_array($result); $_POST['username'] = $check_rows['username']; $_POST['password'] = $check_rows['password']; echo "<center>"; echo "You are now Logged In. "; echo "</center>"; } else { echo "<center>"; echo "No User found. "; echo "</center>"; } } else echo "Error"; ?> </head> <body> <form method="post"> Username : <input name="username" placeholder="Enter Username" type="text"><br></br> Password : <input name="password" placeholder="Enter Password" type="password"><br> <input type="submit" value="Submit"> </body> </html>

Answer 1

您希望获取名为$_POST的{{1}}，但不要将其发送到表单

尝试更改

submit

到

<input type="submit" value="Submit">

Answer 2

首先这是旧式的php / mysql。所以看看php.net上的PDO看到你正在开始新项目，现在变得非常难以做出改变而不是更晚。

现在谈谈你的问题。如果你打算继续用你的旧方法试试这个。

$sql = "SELECT * FROM user WHERE username=' . $username . ' AND password=' . $password . '";

// check the query with the die & mysql_error functions
$query = mysql_query($sql) or die(mysql_error());
$result = mysql_num_rows($query);

// checking here equal to 1 In a live case, for testing you could use >= but not much point.
if ($result == 1) {

    // Checking needs to be Assoc Now you can use the field names, 
    // otherwise $check_rows[0], $check_rows[1] etc etc
    $check_rows = mysql_fetch_assoc($query); // oops we all make mistakes, query not result, sorry.

    // This is bad but for example il let this by, 
    // please dont access user supplied data without
    // validating/sanitising it.        
    $_POST['username'] = $check_rows['username']; 
    $_POST['password'] = $check_rows['password'];

} else {

    // do not logged in here

}

PDO中的相同

$sql=" Your query here ";
$pdo->query($sql);
$pdo->execute();
$result = $pdo->fetch();

if ($result = 1) {
    // do login stuff
} else {
    // no login
}

请记住，您需要设置PDO，默认情况下它可能在您的服务器上不可用（较旧的php / mysql版本），但您的主机应该很高兴设置它们。

登录页面未连接到注册页面

2 个答案: