Negative integers

[Porl123]

I've been making this function which checks if the value isn't a decimal, which works. Then I've put is_numeric in there and checked that the value is >= 1 because all I want the user to enter is a whole, numeric, positive number. But for some reason it still allows the user to enter values with a minus on the end e.g. 010000000000000-

I'm not really sure at all why it allows them to do that. If someone could help me out with what I'm missing it would be greatly appreciated. Thanks

[Mchl]

Show us your code?

[Porl123]

Woops, sorry forgot that

 

function whole_int($var) {

$var = (int)$var;

if($var >= 1 && is_numeric($var)) {

$tmp = explode('.', $var);

$var = (is_array($tmp)) ? $tmp[0] : $var;

} else {

$var = 0;

}

 

return $var;

}

[wildteen88]

I've been making this function which checks if the value isn't a decimal, which works. Then I've put is_numeric in there and checked that the value is >= 1 because all I want the user to enter is a whole, numeric, positive number. But for some reason it still allows the user to enter values with a minus on the end e.g. 010000000000000-

I'm not really sure at all why it allows them to do that. If someone could help me out with what I'm missing it would be greatly appreciated. Thanks

Numbers which end with a minus are not negatives, negatives start with a minus.

 

Also when you do

$var = (int)$var;

(int) will remove any non-numeric characters from $var, eg

$var = '123abc456';
echo (int) $var;

PHP will return $var as 123

[DarkWater]

I don't know why you have that whole function going on, when you could just do:

 

$number = 64.5;
$number = (int) $number; //now it's 64
echo abs($number); //handles negatives

[Psycho]

I agree with Wildteen and Darkwater that you can convert the value to an integer and then just validate that it is greater than 0.

 

However, in some instances changing the users entered value like that can be problematic and you should have them correct it themselves. The easiest solution for that (in my opinion) would be a simple regular expression check

<?php

  if (!preg_match("/[^\d]/", $_POST['thevalue'])) { 
    echo "Valid";
  } else {
    echo "Not Valid";
  }

?>

 

The value must contain only numbers (0-9) and cannot contain decimals, negative signs, etc.

[Porl123]

Ah that's got it working fine now thanks guys for your help