No 'Access-Control-Allow-Origin' header is present on the requested Resource. Origin 'null' is therefore not allowed access. - Phonegap

Question

I’ve been reading about this json method and I just don’t understand and don’t know what to fix, I’m using another domain to get the json.

Here is my code:

$(function(){
    var url = "http://website.com/json.php";
    $.getJSON(url, function(result) {
        console.log(result);
        $.each(result, function(i, field) {
            var id = field.id;
            var title = field.title;
            $(".class").append("<a href='page.html?id=" + id + "&title=" + title +");
        });
    });
});

Error:

Xmlhttprequest cannot load http://website.com/json.php. No 'Access-Control-Allow-Origin' header is present on the requested Resource. Origin 'null' is therefore not allowed access.

How can I pass this to another code, like this:

 $.ajax({
        url: url,
        crossDomain: true,
        data: form,
        dataType: 'json',
        success: function(data) {
            console.log(data);
        },
        type: 'POST'
    });

Json.php:

<?php
    header("Access-Control-Allow-Origin: *");
    include "db.php";
    $data=array();
    $q=mysqli_query($con,"select * from `course_details`");
    while ($row=mysqli_fetch_object($q)){
        $data[]=$row;
    }
echo json_encode($data);
?>

Db.php

<?php
    header("Access-Control-Allow-Origin: *");
    $con = mysqli_connect("localhost","user","pass","db") or die ("could not connect database");
?>

I am opening index.html by Chrome itself, not by localhost, and I am calling on another domain (website.com/json.php), and you have this problem.

A staff put as duplicate. , but it is not duplicated, I would like a solution that in the other has no, accurate has a clear answer.

Answer 1

If you don’t have access to the server to add headers:

You can use one of the extensions for Chrome (for development):

Allow-Control-Allow-Origin: *

CORS Toggle

These extensions disable Chrome security with respect to communication from different hosts and without the authorization setting in the header (as done by the header function() ).

In short this error is fixed by adding: (PHP)

header("Access-Control-Allow-Origin: *");
header("Access-Control-Allow-Headers: Content-Type");
echo json_encode($data);

Or your API-consuming front end must be on the same host(IP+port) as your API.

Answer 2

Everything indicates that it is a communication problem with the server of your site. This occurs when you try to make a call to a server that is in a domain other than the origin of your request. I don’t know what technology you are using on your site, but it is possible to enable this communication.

Search on how to enable CORS on the technology you are using on the site.