More concise way to check to see if an array contains only numbers (integers)
Solution 1:
$only_integers === array_filter($only_integers, 'is_int'); // true
$letters_and_numbers === array_filter($letters_and_numbers, 'is_int'); // false
It would help you in the future to define two helper, higher-order functions:
/**
* Tell whether all members of $array validate the $predicate.
*
* all(array(1, 2, 3), 'is_int'); -> true
* all(array(1, 2, 'a'), 'is_int'); -> false
*/
function all($array, $predicate) {
return array_filter($array, $predicate) === $array;
}
/**
* Tell whether any member of $array validates the $predicate.
*
* any(array(1, 'a', 'b'), 'is_int'); -> true
* any(array('a', 'b', 'c'), 'is_int'); -> false
*/
function any($array, $predicate) {
return array_filter($array, $predicate) !== array();
}
Solution 2:
<?php
$only_integers = array(1,2,3,4,5,6,7,8,9,10);
$letters_and_numbers = array('a',1,'b',2,'c',3);
function arrayHasOnlyInts($array){
$test = implode('',$array);
return is_numeric($test);
}
echo "numbers:". $has_only_ints = arrayHasOnlyInts($only_integers )."<br />"; // true
echo "letters:". $has_only_ints = arrayHasOnlyInts($letters_and_numbers )."<br />"; // false
echo 'goodbye';
?>
Solution 3:
Another alternative, though probably slower than other solutions posted here:
function arrayHasOnlyInts($arr) {
$nonints = preg_grep('/\D/', $arr); // returns array of elements with non-ints
return(count($nonints) == 0); // if array has 0 elements, there's no non-ints
}
Solution 4:
There's always array_reduce():
array_reduce($array, function($a, $b) { return $a && is_int($b); }, true);
But I would favor the fastest solution (which is what you supplied) over the most concise.