PHP session, multiple pages linking to one page

问题

Okay, so I just noticed this issue. There has to be a way around it.

Example... On page A.php and on page B.php, there is a link to page ALPHABET.php. ALPHABET.php receives specified variable values depending on which page is the referrer.

All pages involved have session_start(); at the beginning.

Page A.php has:

           <?php 
                $_SESSION['name'] = "John";
           ?>

Page B.php has:

           <?php 
                $_SESSION['name'] = "Jane";
           ?>

Page ALPHABET.php has:

           <?php
                $personName = $_SESSION['name'];
                echo "Hello, I am ".$personName;
           ?>

I decided not to close the session in ALPHABET.php, because I want the information to still load correctly if some refreshes the page. If session were closed, then $_SESSION['name'] wouldn't exist or have a value.

This all worked fine and good, until I loaded both pages, A.php and B.php, at the same time (via new tab). I noticed that the when I click the link to ALPHABET.php on either of these pages, it doesn't always take the session info from the page that was the referrer. I noted that in this situation, the last page that loaded will have its information displayed in ALPHABET.php, instead of the page from which I clicked the link.

i.e. I load both pages up. First A.php and then I open B.php in a new tab. I click on the ALPHABET.php link inside of A.php. ALPHABET.php loads B.php's information. I assume this is because B.php was the last page to load and therefore it overwrote all session data from A.php and replaced it with its own.

Is there a fix for this?

回答1:

PHP sessions are stored in cookies, which are shared between all tabs of a browser. E.G. there's not a good way to get around this simply by using vanilla sessions.

One effective way, however, would be to store the information in two separate variables and then put a GET request that is specific to each referrer.

E.g.

A.php

$_SESSION["A_name"] = "John";
?>

<a href="Alphabet.php?ref=A">Click</a>

B.php

$_SESSION["B_name"] = "Jane";
?>

<a href="Alphabet.php?ref=B">Click</a>

Alphabet.php

if($_GET["ref"] == "A")
    echo $_SESSION["A_name"];
else if($_GET["ref"] == "B")
    echo $_SESSION["B_name"];

来源：https://stackoverflow.com/questions/29338262/php-session-multiple-pages-linking-to-one-page

标签

php

variables

session

overwrite