Get the value of a variable in page1.php in page2.php - php

Question

I have a question about how I can access the value from a variable from one page on another one.
I have a registration script and the registration form is on my homepage. I want to dynamically create a random name for every input field (change the value of the name attribute). The current name attribute for the input is just firstName, but I want it to be like firstName_345635. The 345635 is a randomly generated number and will change everytime the page refreshes.
Here is my random number variable:
$firstNameInputName = 'firstName_' . rand(10000, 50000);
The output becomes: firstName_[randomNumer].
The problem is, the register.php has all the post variables to get the form data. What I have now is this:
$firstName = $_POST["firstName"]);
I need to get the value from the random number variables from the homepage and instead of giving the $firstname variable the name firstName, it should get the name that the random number generating variable has produced on the homepage.
How can I achieve this?

Answer 1

You should use a session (or cookies) var to save this dynamic name.
Approach 1. Session (or cookies)
page1.php
<?php
session_start();
$customCode = rand(5, 15);
$_SESSION['customCode'] = $customCode; ?>
<form action="page2.php" method="post">
<input type="text" name="firstName_<?php echo $customCode; ?>" />
</form>
page2.php
<?php
session_start();
$customCode = $_SESSION['customCode']; ?>
$firstName = $_POST['firstName_'.$customCode];
Approach 2. You can put a input hidden field in your form like:
<input type="hidden" name="customCode" value="345635" />
And get it in second page like:
$firstName = $_POST['firstName_'.$_POST['customCode']];
Approach 3. You can iterate over your $_POST array to get firstName like:
foreach($_POST in $key => $value) {
if(strpos($key, "firstName")) {
$firstName = $value;
}
}

Answer 2

The solution is sessions, session variables are superglobal variables which means you can use them in different files as long as its the same session, to use them you need to start the session at every page you'll use them in, also, starting the session has to be done before any output is shown.
Ex (registeration page):
<?php
session_start();
/**
** HTML AND FORM HERE WHATEVER ELSE YOU NEED TO DISPLAY
**/
$_SESSION['FirstName'] = $firstNameInputName;
?>
Ex (processing page):
<?php
session_start();
echo $_POST[$_SESSION['FirstName']]; // Output: Whatever was entered inside the field
?>