is_numeric

Example-is-numeric.php

<?php


$numbers = array(
	12,
	1551,
	'21',
	'5115',
	'I am a string',
);


//loop through the numbers array
foreach( $numbers as $number ){
	
	//filter if it is a number or a numeric string 
	if( is_numeric( $number ) ){
		
		echo $number . ' is numeric.' . "</br>";
		
	//otherwise output value is not a number 	
	} else {
		
		echo $number . ' is not number.' . "</br>"; 
	
	}
}

?> 

*****Output*****
12 is numeric.
1551 is numeric.
21 is numeric.
5115 is numeric.
I am a string is not number.
****************