不能无法获取JSON文件跨域

Question

I generate a list of objects in a json file using PHP and then i used jQuery to get data from it

    $.ajax({
        url: url,
        method: "get",
        dataType: "json"
        }).done(function (data) {
                for(var i=0; i < data.length; i++){
                document.getElementById("id01").innerHTML = data[i].Kategorianimi;

    }
    }).fail(function () {
        document.getElementById("id01").innerHTML = "cant get json";
    })

});

It worked ok in localhost but when i give a external host link to the url, it not work. Is there anyone has same issue with me and could you guy show me how to fix it? thanks.

When i add a header like this, then my JSON data was error

<?php
require_once "../pdo/kategoriaPDO.php";
header('Access-Control-Allow-Origin: *’);

/**
 * Created by PhpStorm.
 * User: dinhthinh
 * Date: 27/11/16
 * Time: 14:07
 */
$katepdo = new KatePDO();
$json = str_replace("\u0000","",json_encode($katepdo->listaKaikkiKategoriat(), true));
echo stripcslashes($json);

Answer 1

You must add your host to server's Access-Control-Allow-Origin header, or just send Access-Control-Allow-Origin: * header from server