how to use checkbox for selected data from the retrieved json data

I am using php curl to connect to my API, i want only retrieve the "item_name" and "item_id" and allow to choose what they want from the retrieved data via check box.

How can I make a check box for every "item_name" from the JSON or JSON_DECODE data.

I have tried many array search and key_exist function however was still unable to succeed, I need to store all item_id and item_name perhaps in a separate array for further use

$data = array(
 "query" => "Cookies `n Cream?",
 "appId" => "",
 "appKey"=> ""
 );

    $data_string = json_encode($data);                                                                                   
    $url_1='http://ift.tt/1KlYKM7';    


    function sendfunc($url, $post){
    $ch=curl_init();                                                             
    curl_setopt($ch, CURLOPT_URL,$url);
    curl_setopt($ch, CURLOPT_POST, false);
    curl_setopt($ch, CURLOPT_HTTPHEADER, array(
        'Content-Type: application/json'
    ));
     curl_setopt($ch, CURLOPT_POSTFIELDS,$post);

     $result = curl_exec($ch);
    curl_close($ch);
    global $result_arr;
    $result_arr = (array) json_decode($result, true);
    /* print_r($result_arr); */
    }
    /* " " . sendfunc($url_1, $data_string); */ 

    echo '<form method="post">';
    echo 'foreach {

    <input id="'.$item_arr.'" value="'.$result_arr.'"  name="$item_arr" type="checkbox" >';

    ?>
    }
    <input type="submit">
    </form>

From what I understand is before and after execution the json is stored in an php array however I don't understand why print_r($result_arr) is not working , and that I cannot access $result_arr outside the function hence I made it global even though its bad practice

please illustrate your explanation or suggestions by examples