php - Controlling the output of a json feed -

i'm trying pull out json feed wordpress query. need json formatted [{"id":"1","title":"title"},{"id":"2","title":"title2"}]

the json_encode function not pulling out specific format: items not separated commas , i'm missing initial , final [ ]

i made code echoing missing elements, works good, final comma, because of echo making script reading fail.

<?php  $args = array(     'post_type' => 'location',     'posts_per_page' => -1 );  $locations = new wp_query($args);      if($locations -> have_posts()):         echo '[';         while ($locations->have_posts()) : $locations->the_post();         $coords = get_field('coordinates');         $pid = get_the_id();         $json["id"] = $pid;         $json["name"] = get_the_title();         $json["lat"] = $coords['lat'];         $json["lng"] = $coords['lng'];         $json["address"] = get_field('address');         $json["address2"] = get_field('address_2');         $json["city"] = get_field('city');         $json["state"] = get_field('state');         $json["postal"] = get_field('zip_code');         $json["phone"] = get_field('office_phone');         $json["fax"] = get_field('office_fax');         $json["web"] = apply_filters('the_permalink', get_permalink());               echo json_encode($json);         echo ',';     endwhile;         echo ']';     endif;  ?> 

i know echoing elements not correct way it, , i'm doing wrong on encode, that's why it's pulling out without right formatting.

i have been researching days , couldn't find way create json_encode echoing , @ same time controlling fields show wordpress query.

i appreciate in advance solution/lead solve this.

you're adding wrong in loop. want create array, , present array json.

if($locations -> have_posts()):     $data = array();     while ($locations->have_posts()) : $locations->the_post();      // add location stuff $data array     $data[] = array(         'id' => $pid,         'name' => get_the_title(),         // etc....     );      endwhile; // present json echo json_encode($data);  endif;