is_int() cannot check $_GET in PHP?
Solution 1
is_int
checks that the data type is an integer, but everything in $_GET
will be a string. Therefore, it will always return false
.
In a pinch, you could cast to an integer and then check for != 0.
$id = isset($_GET['id']) ? (int) $_GET['id'] : null;
if (!$id) { // === 0 || === null
header('HTTP/1.1 404 Not Found');
exit('404, page not found');
}
But a more robust solution would involve some type of input string validation / filtering, like PHP's built-in filter_input_array()
.
(Edited post on Oct/13 since it is still receiving upvotes and it was somewhat confusingly worded.)
Solution 2
User input in $_GET array (as well as the other superglobals) all take the form of strings.
is_int
checks the type (i.e. string
) of the value, not whether it contains integer-like values. For verification that the input is an integer string, I would suggest either something like ctype_digit
or an integer filter (FILTER_VALIDATE_INT
—this has the benefit of actually changing the value to type integer). Of course you could also typecast it with (int)
.
Solution 3
From the PHP documentation for is_int:
Note: To test if a variable is a number or a numeric string (such as form input, which is always a string), you must use is_numeric().
Solution 4
Any user input comes in as a string, because PHP has no way to tell what data type you expect the data to be.
Cast it to an integer or use a regex if you want to make sure it's an integer.
<?php
$id = $_GET["id"];
if ((int) $id == 0) {
header('HTTP/1.1 404 Not Found');
exit('404, page not found');
}
?>
Solution 5
Try using is_numeric
instead of is_int
. is_numeric
checks to see if it is given something that can be a number ($_GET
returns strings I think). is_int
checks to see if the variable is of type int
![ilhan](https://i.stack.imgur.com/0ivuN.jpg?s=256&g=1)
Comments
-
ilhan almost 2 years
Here is my code:
<?php $id = $_GET["id"]; if (is_int($id) === FALSE) { header('HTTP/1.1 404 Not Found'); exit('404, page not found'); } ?>
It always enters inside the if.