Allow ajax from outside in PHP

myajax.php

if (isset($_SERVER['HTTP_ORIGIN'])){
			header("Access-Control-Allow-Origin: {$_SERVER['HTTP_ORIGIN']}");
			header('Access-Control-Allow-Credentials: true');
			header('Access-Control-Max-Age: 86400');    // cache for 1 day
		}

		// Access-Control headers are received during OPTIONS requests
		if ($_SERVER['REQUEST_METHOD'] == 'OPTIONS') 
		{

			if (isset($_SERVER['HTTP_ACCESS_CONTROL_REQUEST_METHOD']))
				header("Access-Control-Allow-Methods: GET, POST,OPTIONS");         

			if (isset($_SERVER['HTTP_ACCESS_CONTROL_REQUEST_HEADERS']))
				header("Access-Control-Allow-Headers:        {$_SERVER['HTTP_ACCESS_CONTROL_REQUEST_HEADERS']}");

			exit(0);
		}