当我在php中使用以下代码进行注销时间捕获时，屏幕变成白色，时间不会保存在mysqldb中 - when i used the following code for logout time capturing in php the screen turns white and time is not saving in mysql db

when i used the following code for logout time capturing in php the screen turns white and time is not saving in mysql db

// check that the session exists first
if(isset($_SESSION['username'])) {
// you should put your db connection in a config.php file and use mysqli or PDO - what you're using is depreciated
mysql_connect("localhost", "root", "") or die("cannot connect"); 
mysql_select_db("logtime") or die("cannot select DB");
// don't think I'd store password in a session...
// also, is username UNIQUE in your database?
// also, also, ALWAYS escape (sanitize) your database input to prevent agains SQL injection
$sql = "SELECT username, password 
FROM 
    users 
WHERE 
    username = '".mysql_real_escape_string($_SESSION['username'])."' 
AND 
    password = '".mysql_real_escape_string($_SESSION['password'])."'";
$result = mysql_query($sql) or die('sql: '.mysql_error()); 
if(mysql_num_rows($result) > 0) {
    $sql_2 = "INSERT INTO exit1(username, outtime) VALUES ('".mysql_real_escape_string($_SESSION['username'])."', NOW())";
    mysql_query($sql_2) or die('sql2: '.mysql_error()); 
    session_destroy();
    header("location: index.php");
} else {
    echo 'There was an error. You have not been logged out.';
}

}

这里的问题是，当我点击注销按钮时，时间没有保存在数据库中，屏幕变成白色。有什么想法吗？

打开错误报告。另外，您在session_start()之前调用session_destroy()和$_SESSION[]。请查看此处的示例。

不要使用mysql_*函数，它们已被弃用。使用PDO或mysqli_*。

不要在数据库中存储原始密码。使用password_hash()和password_verify()函数(md5不用于密码哈希(。

此代码用于session.php

<?php
// Establishing Connection with Server by passing server_name, user_id and password as a parameter
$connection = mysqli_connect("localhost", "root", "");
// Selecting Database
$db = mysqli_select_db($connection, "logtime");
session_start();// Starting Session
// Storing Session
$user_check=$_SESSION['login_user'];
// SQL Query To Fetch Complete Information Of User
$ses_sql=mysqli_query($connection, "select username from users where username='$user_check'");
$row = mysqli_fetch_assoc($ses_sql);
$login_session =$row['username'];
if(!isset($login_session)){
mysql_close($connection); // Closing Connection
header('Location: index.php'); // Redirecting To Home Page
}
?>

该代码用于在mysql 中捕获注销时间

<?php
include('session.php');
mysqli_query($connection,"INSERT INTO exit1(id, username, outtime) VALUES ('', '$login_session', NOW())");
header('Location: index.php');
session_destroy();
?>