Home > Article > Backend Development > Code example for php user login detection

Code example for php user login detection

WBOYOriginal: 2016-07-25 08:56:491063browse

This article shares a simple PHP user login code, which checks whether the username and password are valid by comparing them with the values stored in the array. Friends in need can use it as a reference.

First, store the username and password in an array. When a user logs in, the value is taken from the array to participate in the detection to determine whether the username and password are valid.

<HTML>
<BODY>
<FORM METHOD="POST" ACTION="LoginFormAction.php">
<H2>用户登录</H2>
<BR><BR>
用户名:
<BR><INPUT TYPE="TEXT" NAME="username" SIZE="16">
<BR><BR>
密 码:
<BR><INPUT TYPE="PASSWORD" NAME="password" SIZE="16">
<BR><BR> <BR><BR>
<INPUT TYPE="SUBMIT" VALUE="Submit">
</FORM>
</BODY>
</HTML>
<!-- LoginFormAction.php
<?php
$passwords = array("name1"   =>"pass1", 
                   "name2"   =>"pass2");
                   
if ($password == $passwords[$username]){
    setcookie("username", $username, time()+1200);
    echo "<H2>登录成功.</H2>";
}else{
    setcookie("username", "", time()-3600);
    echo "<H2>禁止登录：无效的用户名或密码</H2>";
}
?>
-->

2. The following code implements user login detection through a custom php function. It can detect the length of username and password and whether the username and password are correct.

Code:

<?php
//验证用户登录
//by bbs.it-home.org
function validate_user ($username, $password){
    return true;
}
   
// create empty array to store error messages
$errors = array();
$p =& $_POST;
   
if (count ($p) > 0){
     if (!isset ($p['username']) || (trim ($p['username']) == '')){
          $errors[] = 'You must enter a username.';
     }elseif{ ((strlen ($p['username']) < 8) || (ereg ('[^a-zA-Z0-9]', $p['username']))){
          $errors[] = '用户名无效，请输入至少8位的用户名，且只能包含字母与数字的组合。';
     }
     
     if (!isset ($p['password']) || (trim ($p['password']) == '')){
          $errors[] = 'You must enter a password.';
     }elseif ((strlen ($p['password']) < 8) || (ereg ('[^[:alnum:][:punct:][:space:]]', $p['password']))){
          $errors[] = '密码无效，请输入至少8位的密码，且只能包含字母、数字、标点与空格的组合。';
     }
     
     if (count ($errors) == 0) {
          $r = validate_user ($p['username'], $p['password']);
   
          if ($r == false){
               $errors[] = '登录失败，用户名与密码错误。';
          } else {
               print ('<html><head><title>登录成功</title></head>
                      <body><h1>祝贺你</h1><p>成功登录!</p>
                      </body></html>');
               exit;
          }
     }
}
?>
<html>
<head><title>用户登录</title></head>
<body>
<h1>用户登录</h1>
<?php
     if (count ($errors) > 0) {
          $n = count ($errors);
          for ($i = 0; $i < $n; $i++){
               print '<br /><font color="red">' . $errors[$i] . '</font>';
          }     
     }
?>
<form action="<?php print ($PHP_SELF); ?>" method="POST">
     <table>
     <tr><td>Username:</td>
     <td><input type="text" name="username" value="<?php if (isset ($p['username'])) print $p['username']; ?>" /></td>
     </tr>
     <tr><td>Password:</td>
     <td><input type="text" name="password" value="<?php if (isset ($p['password'])) print $p['password']; ?>" /></td>
     </tr>
     <tr><td colspan="2"><input type="submit" name="submit"></td></tr>
     </table>
     <input type="hidden" name="__process_form__" value="1" />
</form>
</body>
</html>

Statement：

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Previous article：A useful php mysql connection classNext article：A useful php mysql connection class

See more

Code example for php user login detection

Related articles