PHP validate float via IS_FLOAT

Question

I need to validate inputs - find out, if inputs are float. According to websites, my code should work, but it doesnt.

<?php
$new_estimate=array("3.3","10.3","1.1","2.35");
$mistake="no";

for ($i=0; $i<(sizeof($new_estimate)); $i++)
    {
       if (!is_float($new_estimate[$i]))
         {
         $mistake="yes";
         }
    }

echo $mistake;
?>

I think all values of array are float, but browser shows "yes" - instead my expectation. I dont understand, why it doesnt work.

Those are strings not floats. $new_estimate=array(3.3,10.3,1.1,2.35); A var_dump() would show you this. — AbraCadaver
– AbraCadaver, Commented Dec 12, 2014 at 21:59
Looking for FILTER_VALIDATE_FLOAT perhaps, when the sample array is meant to be form input? — mario
– mario, Commented Dec 12, 2014 at 22:02
you can update existing code like this if (!is_float((float) $new_estimate[$i])) — saqibahmad
– saqibahmad, Commented Dec 12, 2014 at 22:06
@saqibahmad If you cast to float, it's bound to be a float so testing for that will not do much... — jeroen
– jeroen, Commented Dec 12, 2014 at 22:08

Danijel · Accepted Answer · 2014-12-12 22:12:13Z

2

It is because is_float() checks if the type of a variable is float, and you are working with an array of string values. To validate inputs you can use filter_var() as in example below.

$new_estimate = array( "3.3", "10.3", "1.1", "2.35" );

$mistake = (bool) array_filter( $new_estimate, function( $item ) {
    return !filter_var( $item, FILTER_VALIDATE_FLOAT );
});

answered Dec 12, 2014 at 22:12

Danijel

12.8k5 gold badges43 silver badges57 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

dersvenhesse · Accepted Answer · 2014-12-12 22:02:26Z

1

This are strings in your array, if you'd like them to be floats remove the " around the numbers. If you intend to check for numbers instead of the concrete type, use is_numeric (Documentation).

$new_estimate = array(3.3, 10.3, 1.1, 2.35);

Furthermore, instead using the strings "yes" and "no" for $mistake, set them true or false and use the variable as a boolean.

answered Dec 12, 2014 at 22:02

dersvenhesse

6,4642 gold badges34 silver badges55 bronze badges

Collectives™ on Stack Overflow

PHP validate float via IS_FLOAT

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related