How to list categories and subcategories in JSON format?

I need to integrate this plugin with my WordPress site, and the categories must be in this format:

 "Option 1": {"Suboption":200},
 "Option 2": {"Suboption 2": {"Subsub 1":201, "Subsub 2":202},
                "Suboption 3": {"Subsub 3":203, "Subsub 4":204, "Subsub 5":205}
               }

How can I get that?
I tried the options of the json-api.

And this is the walker:

class MyWalker extends Walker_Category {
    var $tree_type = 'category';

    var $db_fields = array ('parent' => 'parent', 'id' => 'term_id');

    function start_lvl( &$output, $depth, $args = array() ) {
        if ( 'list' != $args['style'] )
            return;

        $indent = str_repeat("\t", $depth);
        $output .= "$indent:{";
    }

    function end_lvl( &$output, $depth, $args = array() ) {
        if ( 'list' != $args['style'] )
            return;

        $indent = str_repeat("\t", $depth);
        $output .= "$indent}\n";
    }

    function start_el($output, $category, $depth , $args = array() ) {
        extract($args);
        $cat_name = esc_attr( $category->name );
        $cat_name = apply_filters( 'list_cats', $cat_name, $category );
        $output .= '"' . $cat_name.'=>'.$depth . '",';
    }

    function end_el($output, $page, $depth = 0, $args = array() ) {
        if ( 'list' != $args['style'] )
            return;

        $output .= "\n";
    }
}

I need to integrate this plugin with my WordPress site, and the categories must be in this format:

 "Option 1": {"Suboption":200},
 "Option 2": {"Suboption 2": {"Subsub 1":201, "Subsub 2":202},
                "Suboption 3": {"Subsub 3":203, "Subsub 4":204, "Subsub 5":205}
               }

How can I get that?
I tried the options of the json-api.

And this is the walker:

class MyWalker extends Walker_Category {
    var $tree_type = 'category';

    var $db_fields = array ('parent' => 'parent', 'id' => 'term_id');

    function start_lvl( &$output, $depth, $args = array() ) {
        if ( 'list' != $args['style'] )
            return;

        $indent = str_repeat("\t", $depth);
        $output .= "$indent:{";
    }

    function end_lvl( &$output, $depth, $args = array() ) {
        if ( 'list' != $args['style'] )
            return;

        $indent = str_repeat("\t", $depth);
        $output .= "$indent}\n";
    }

    function start_el($output, $category, $depth , $args = array() ) {
        extract($args);
        $cat_name = esc_attr( $category->name );
        $cat_name = apply_filters( 'list_cats', $cat_name, $category );
        $output .= '"' . $cat_name.'=>'.$depth . '",';
    }

    function end_el($output, $page, $depth = 0, $args = array() ) {
        if ( 'list' != $args['style'] )
            return;

        $output .= "\n";
    }
}

• categories
• json

Share Improve this question edited Jan 17, 2013 at 0:54 brasofilo 22.2k88 gold badges7070 silver badges270270 bronze badges asked Jan 16, 2013 at 23:41 AminoAmino 32322 gold badges55 silver badges1717 bronze badges 3

• 2 Can't you build your custom array and do a json_encode? – brasofilo Commented Jan 17, 2013 at 0:15
• @brasofilo It will change (categories), how can I make custom array dynamically? – Amino Commented Jan 17, 2013 at 0:33
• I really don't understand what is the heart of the problem, what does that jQuery Option Tree has to do with the JsonAPI plugin or the Walker_Category... I think, in general sense, every line of code is dynamic, so once again: check the PHP Manual. – brasofilo Commented Jan 17, 2013 at 1:01

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2 Answers 2

Sorted by: Reset to default 0

Here is a fast example using get_categories instead of a plugin or the walker class, maybe it will help you in the right direction, it will list all children of a parent category in json format. As brasofilo mentions since you require a specific format you will want to build a custom array.

// let's get the bare minimum going
$args = array(
    'type'                     => 'post',
    'child_of'                 =>  20, //change this, hardcoded as example
    'taxonomy'                 =>  'category'
);

$categories = get_categories( $args );
$json = json_encode($categories);

var_dump($json); //do what you want

$args = [
    'taxonomy' => 'category',
    'hide_empty' => 0,
    'parent' => 0
];

function _get_child_terms( $items ) {
    foreach ( $items as $item ) {
      $item->children = get_terms( 'category', array( 'child_of' => $item->term_id, 'hide_empty' => 0 ) );
      if ( $item->children ) _get_child_terms( $item->children );
    }
    return $items;
}

$terms = _get_child_terms( get_terms( $args ) );
echo json_encode( $terms );