PHP数据库不会保存数据

Question

我从视频教程系列中获得了以下代码。 （我听说下面代码的某些部分被认为是不好的做法......）。 我一直试图让它保存我的注册信息，但它只是不起作用。 它会在填写表格时发现错误，它还会显示“请登录以开始”！ 当我正确提交所有内容时，它只是不会将任何数据保存到数据库中：

PHP

<?php include ("./inc/connect.inc.php"); ?>
    <?php
    $reg = @$_POST['reg'];
    //declaring variables to prevent errors
    $fn = ""; //First Name
    $ln = ""; //Last Name
    $un = ""; //Username
    $em = ""; //Email
    $em2 = ""; //Email 2
    $pswd = ""; //Password
    $pswd2 = ""; //Password 2
    $d = ""; //Sign up date
    $u_check = ""; //Check if username exists
    //registration form
    $fn = strip_tags(@$_POST['fname']);
    $ln = strip_tags(@$_POST['lname']);
    $un = strip_tags(@$_POST['username']);
    $em = strip_tags(@$_POST['email']);
    $em2 = strip_tags(@$_POST['email2']);
    $pswd = strip_tags(@$_POST['password']);
    $pswd2 = strip_tags(@$_POST['password2']);
    $d = date("Y-m-d"); //Year - Month - Day

    if ($reg) {
    if ($em==$em2) {
    // check if user already exists
    $u_check = mysqli_query($link,"SELECT username FROM users WHERE username='$un'");
    // count the amount of rows where username = $un
    $check = mysqli_num_rows($u_check);
    if ($check == 0) {
    // check all of the fields have been filled
    if ($fn&&$ln&&$un&&$em&&$em2&&$pswd&&$pswd2) {
    // check that passwords match
    if ($pswd==$pswd2) {
    // check the maximum length of username, first, and last name does not exceed 25 characters
    if (strlen($un)>25||strlen($fn)>25||strlen($ln)>25) {
    echo "The maximum limit for username, first, and last name is 25 characters!";
    }
    else
    {
    // check the length of password does not exceed 30 characters and is no less than 5 characters
    if (strlen($pswd)>30||strlen($pswd)<5) {
    echo "Your password must be between 5 and 30 charcters long!";
    }
    else
    {
    // encrypt password and password 2 using md5 before sending to database
    $pswd = md5($pswd);
    $pswd2 = md5($pswd2);
    $query = mysqli_query($link,"INSERT INTO users VALUES ('','$un','$fn','$ln','$em','$pswd','$d','0')");
    die("<h2>Welcome to findFriends</h2> Please login to get started!");
    }
    }
    }
    else {
    echo "Your passwords do not match!!";
    }
    }
    else {
    echo "Please Fill in all required fields.";
    }
    }
    else {
    echo "Sorry, that username is not available.";
    }
    }
    else {
    echo "Your email does not match!";
    }
    }
    ?>

HTML

<div style="width: 200px; margin-left: 550px; margin-top: 20px;">
        <table>
            <tr>
                <td width="90%" valign="top">
                    <h2>Join findfriends Today!</h2>
                </td>
                <td width="40%" valign="top"></td>
                    <h2>Sign Up Below!</h2>
                    <form action="index.php" method="POST">
                        <input type="text" name="fname" size="25" placeholder="First Name"><br /><br />
                        <input type="text" name="lname" size="25" placeholder="Last Name"><br /><br />
                        <input type="text" name="username" size="25" placeholder="Username"><br /><br />        
                        <input type="text" name="email" size="25" placeholder="Email"><br /><br />
                        <input type="text" name="email2" size="25" placeholder="Email"><br /><br />
                        <input type="text" name="password" size="25" placeholder="Password"><br /><br />
                        <input type="text" name="password2" size="25" placeholder="Password (again)"><br /><br />
                        <input type="submit" name="reg" value="Sign Up!">           
                    </form>
            </tr>
        </table>
</div>
</body>
</html>

MYSQL （添加到phpmyadmin）

CREATE TABLE IF NOT EXISTS `users` (
  `id` int(11) NOT NULL AUTO_INCREMENT, /* AUTO_INCREMENT = 1st user, id 1, 2nd user, id 2....*/
  `username` varchar(255) NOT NULL,
  `first_name` varchar(255) NOT NULL,
  `last_name` varchar(255) NOT NULL,
  `email` varchar(255) NOT NULL,
  `password` varchar(32) NOT NULL,
  `sign_up_date` date NOT NULL,
  `activated` enum('0','1') NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=1;

和connect.inc.php ：

  <?php
    $link = mysqli_connect('localhost', 'user', 'pswd', 'socialnetwork') or die ("Couldn't connect to SQL server");
    ?>

Answer 1

最好的建议是你要看http日志文件（错误和访问日志）来找到解决方案。