[RESOLVED] passing variables between php pages

[IceRegent]

I am trying to understand how I can pass a variable, such as $message="Login Failed - Please try again" to another header redirected page, and echo out the variable on the new php page. How does one accomplish such a task?

thanks
Ice

[jlucas]

you create a link

$url = "http://www.someplace.com/page.php";

Then add to the end the variable name, WITH a question mark

$url = "http://www.someplace.com/page.php?message";

Then you add the text/message that you want to pass to the other page. But first you need to run the value of $message through urlencode()

$message = "Hi there. How are you?";

$message = urlencode($message);

$url = "http://www.someplace.com/page.php?message=".$message;

now echo the value of $url like this:

<?php

echo "<a href='".$url."'>Link text</a>";

?>

in the outputted HTML, you will see something like
Hi+there%2C+how+are+you%3F

<?php
$message = "Hi there, how are you?";

echo urlencode($message);
//urlencode() will result in this
//Hi+there%2C+how+are+you%3F

echo rawurlencode($message);
//rawurlencode() will result in this
//Hi%20there%2C%20how%20are%20you%3F

?>

Make sure that you use the corresponding decode function on/in the page that you are sending the message to.

urldecode()
or
rawurldecode()

[Drakla]

jlucas wrote:

Make sure that you use the corresponding decode function on/in the page that you are sending the message to.

urldecode()
or
rawurldecode()

Nope, no need for that, it's done for you. You do encode it to pass it through the link, but the decoding is already done for you, so you'd be double decoding it.

[IceRegent]

Ok, there must be other ways to pass variables between pages. Other websites need to pass more than just a simple message between pages, and I dont see all of them using the aforementioned method. I have at least 4-5 variables that I need to keep up from page to page. I saw a mention elsewhere of using session variables between pages. I just cannot find any reference to how to utilize them.

Ice

[Houdini]

Just assign variables to the $SESSION array like;

$_SESSION['var'] = $val;

Make sure that you have started the session with session_start()

[IceRegent]

Egads, Houdini, you are a freakin genious! Heheh. You told me just what I needed to know, I was able to utilize it and this works like a champ. My web site is really starting to take shape now, and this is one of the sticklers that has been bothering me, the ability to keep and pass variables thruout the users session. Now I just gotta learn the rest of the teqniques to close the session properly etc.

Thanks!
Ice

[bradgrafelman]

Another thing you could do, is create a constants file, like:

<?PHP //constants.php

$error = array();

$error[1] = 'Invalid Username.';
$error[2] = 'Invalid Password.';
$error[3] = 'Invalid Action.';
// etc.
?>

Then, when you need to pass an error message, just append '?error=2' to the query string, and have a custom error function like so:

require_once 'constants.php';

$errnum = intval($_GET['error']);
if(isset($error[$errnum])) {
    echo 'Error: ' . $error[$errnum];
} else {
    echo 'Error: Unknown error.';
}

[Sayian]

Another method, one less outgoing is this ..

Page that errors

// im just building an error

$var = 0;

if($var == 0) {

  header("Location: /another_page.php?error=1");
  exit;

}

another_page.php

if(isset($_GET['error']) AND $_GET['error'] == 1) {

   echo "woah man, this is error 1";

}

Hope this helps.