Predefining $_GET parameter on open of index.php - php

Question

Is there a way to set a $_GET parameter with certain value on open of "index.php"
For example: the url being = ".../index.php?somePara=value"
I tried using :
header("Location: index.php?page=1");
exit();
But I get an error of
"localhost redirected you too many times."
Edit:
Thanks, Qirel, that works, I need it because i have variables that are attached to $_GET parameter, so instead of setting them to NULL and then passing value to them after a if($_GET) check -> so that they wont get an error of undefined, I was wondering how pass value on open of the file.

Answer 1

The problem is either that you do not have a condition, or you have, but it is always true in this use-case.
Your question mentions the condition:
Is there a way to set a $_GET parameter with certain value on open of
"index.php"
but your code does not contain that:
header("Location: index.php?page=1");
exit();
So you can wrap this into a condition:
if (isset($_GET["certain"]) && ($_GET["certain"] === "value")) {
header("Location: index.php?page=1");
exit();
}
Note that the string parameter of header does not contain certain, since that would result in an infinite loop. You can also check in the if whether there is a page parameter if you intend to include certain there.
I have read the comment which suggested to set the corresponding key of $_GET to the expected value instead of a redirect, but that is not always an option, since you might want to beautify a URL or even to redirect to another site's page.

Answer 2

If $_GET parameters are used in my code, I always set a default value for these variables since you are never sure if it is set.
$name = isset($_GET['name']) ? $_GET['name'] : 'Guest';
// This is the shorter version for
if (isset($_GET['name'])) {
$name = $_GET['name'];
} else {
$name = 'Guest';
}
Your method of solving your problem will get you into an infinite loop. You could however do:
if (!isset($_GET['page'])) {
header("Location: index.php?page=1");
exit;
}