How to use session and cookie in php to save user logon information at the same time

This article provides a detailed analysis of the implementation code that saves user login information by using session and cookie in php at the same time, for more information, see session and cookie to save user logon information.
1. database connection configuration page: connectvars. php

The code is as follows:

// Database location
Define ('Db _ host', '2017. 0.0.1 ');
// User name
Define ('Db _ user', 'root ');
// Password
Define ('Db _ password', '123 ');
// Database name
Define ('Db _ name', 'test ');
?>

2. logon page: logIn. php

The code is as follows:

// Insert information related to the database connection
Require_once 'connectvars. php ';
// Start a session
Session_start ();
$ Error_msg = "";
// If the user is not logged on, that is, when $ _ SESSION ['User _ id'] is not set, run the following code:
If (! Isset ($ _ SESSION ['User _ id']) {
If (isset ($ _ POST ['submit ']) {// execute the following code when the user submits the logon form
$ Dbc = mysqli_connect (DB_HOST, DB_USER, DB_PASSWORD, DB_NAME );
$ User_username = mysqli_real_escape_string ($ dbc, trim ($ _ POST ['username']);
$ User_password = mysqli_real_escape_string ($ dbc, trim ($ _ POST ['password']);
If (! Empty ($ user_username )&&! Empty ($ user_password )){
// The SHA () function in MySql is used to encrypt strings in one way.
$ Query = "SELECT user_id, username FROM mismatch_user WHERE username = '$ user_username' AND". "password = SHA ('$ user_password ')";
$ Data = mysqli_query ($ dbc, $ query );
// Query with the user name and password. if the record is exactly one, set the SESSION and COOKIE, and redirect the page at the same time.
If (mysqli_num_rows ($ data) = 1 ){
$ Row = mysqli_fetch_array ($ data );
$ _ SESSION ['User _ id'] = $ row ['User _ id'];
$ _ SESSION ['username'] = $ row ['username'];
Setcookie ('User _ id', $ row ['User _ id'], time () + (60*60*24*30 ));
Setcookie ('username', $ row ['username'], time () + (60*60*24*30 ));
$ Home_url = 'loged. php ';
Header ('Location: '. $ home_url );
} Else {// if the record found is incorrect, the error message is set.
$ Error_msg = 'Sorry, you must enter a valid username and password to log in .';
}
} Else {
$ Error_msg = 'Sorry, you must enter a valid username and password to log in .';
}
}
} Else {// if the user has logged on, go directly to the logged on page
$ Home_url = 'loged. php ';
Header ('Location: '. $ home_url );
}
?>


Mismatch-Log In



Msimatch-Log In

If (! Isset ($ _ SESSION ['User _ id']) {
Echo'

'. $ Error_msg .'

';
?>


}
?>

:

3. logon page: loged. php

The code is as follows:

// You must enable the session before using the variable values stored in the session.
Session_start ();
// If the session is not set, check whether the cookie is set.
If (! Isset ($ _ SESSION ['User _ id']) {
If (isset ($ _ COOKIE ['User _ id']) & isset ($ _ COOKIE ['username']) {
// Use cookies to assign values to Sessions
$ _ SESSION ['User _ id'] = $ _ COOKIE ['User _ id'];
$ _ SESSION ['username'] = $ _ COOKIE ['username'];
}
}
// Use a session variable to check the logon status
If (isset ($ _ SESSION ['username']) {
Echo 'you are Logged as '. $ _ SESSION ['username'].'
';
Echo 'log Out ('. $ _ SESSION ['username'].') ';
}
/** On the logon page, you can use the user's session, for example, $ _ SESSION ['username'],
* $ _ SESSION ['User _ id'] queries the database, so you can do a lot of things */
?>

:

4. logOut session and cookie page: logOut. php (redirection to lonIn. php after logOut)

The code is as follows:

/** Cancel the session and cookie simultaneously */
// Even if you log out, you must start the session before accessing the session variable.
Session_start ();
// Use a session variable to check the logon status
If (isset ($ _ SESSION ['User _ id']) {
// To clear the SESSION variable, set the $ _ SESSION Super global variable to an empty array
$ _ SESSION = array ();
// If a session cookie exists, delete it by setting the expiration time to the previous one hour
If (isset ($ _ COOKIE [session_name ()]) {
Setcookie (session_name (), '', time ()-3600 );
}
// Use the built-in session_destroy () function to call and cancel a session
Session_destroy ();
}
// At the same time, set the expiration time of each cookie to a certain time in the past so that they can be deleted by the system, in seconds
Setcookie ('User _ id', '', time ()-3600 );
Setcookie ('username', '', time ()-3600 );
// The location header redirects the browser to another page
$ Home_url = 'login. php ';
Header ('Location: '. $ home_url );
?>