php check if it is digit or letter in string code example

Example 1: check if string is number or not php

$var_num = "1";
$var_str = "Hello World";

var_dump( is_numeric($var_num), is_numeric($var_str) );

/* 
Output -
 bool(true)
 bool(false)
*/

Example 2: php check if string or number

<?php if (is_numeric("cake")) { echo "Yes"; } else { echo "No"; } ?>