php7 how to check, that only int values in html form

Question

this code accepts numbers, e.g. 13.5, 15.6 etc... I need that checked if this is a number only int, e.g. 13, 14 ... etc.

if (is_numeric($r_haslo) == false) {
    $wszystko_ok = false;
    $_SESSION['e_haslo'] = "<i class=\"fas fa-user-times\"></i> Podaj tylko cyfry!";
}

Possible duplicate of [How to check whether a variable in $\_GET Array is an integer?](https://stackoverflow.com/questions/12194205/how-to-check-whether-a-variable-in-get-array-is-an-integer) — O.O.Balance, Jun 14 '18 at 00:16

score 0 · Answer 1 · edited Jun 20 '20 at 09:12

if it has to be an integer and integer only this is how I like to do it.

if (is_numeric($r_haslo) == false || ((int)$r_haslo != $r_haslo)) {
    //is an integer
    $wszystko_ok = false;
    $_SESSION['e_haslo'] = "<i class=\"fas fa-user-times\"></i> Podaj tylko cyfry!";
}

With the updated code above, this now makes sure that $r_haslo is not a number first, and if it is a number, that the number is not an int. So if it's not a number or not an int then it will save the warning to the session.

This way if I send 23 and "23" both are true.
If I send 23 and "23" to is_int() function only 23 will be true.

If you never send string input then is_int() is probably the better way to go.

Update

if (strpos($mystring, ".") || is_numeric($r_haslo) == false || ((int)$r_haslo != $r_haslo)) 
{
    //is an integer
    $wszystko_ok = false;
    $_SESSION['e_haslo'] = "<i class=\"fas fa-user-times\"></i> Podaj tylko cyfry!";
}

The updated code above will also make sure that there is not a '.' in the input.

Note
if the value is being passed as a number, PHP will automatically convert 12.0 and 12. to 12. if the value is being passed as a string, the srtpos() method will catch it.

okay, this is working but i need, that if i press: `12.0` or `12.` that this still does not return the true. so how do I block the possibility of entering a dot? — FSp1333, Jun 13 '18 at 23:07

Progrock · Answer 2 · 2018-06-14T09:22:59.813

0

When you say this code accepts, I'll interpret that as you are taking user input by way of a HTTP POST or GET.

The following will only assign and cast to an integer if the posted string contains digits (an unsigned integer within) otherwise it will be assigned null.

<?php
$id = isset($_POST['id']) && ctype_digit($_POST['id'])
    ? (int) $_POST['id']
    : null;

edited Jun 14 '18 at 09:22

answered Jun 14 '18 at 00:15

Progrock

7,373
1
19
25

score -1 · Answer 3 · answered Jun 13 '18 at 22:32

-1

You can us is_int() to check.

if (is_int($r_haslo) == false) {
    $wszystko_ok = false;
    $_SESSION['e_haslo'] = "<i class=\"fas fa-user-times\"></i> Podaj tylko cyfry!";
}

answered Jun 13 '18 at 22:32

Joseph_J

3,654
2
13
22

3

`is_int()` is false for a string even if it contains the characters of an integer. – Barmar Jun 13 '18 at 22:36

php7 how to check, that only int values in html form

3 Answers3

Update