How do I update a field of a meta box?

Question

While parsing data from a CVS file into a custom post type, i would like to parse data into the fields of a meta box, that I created.

The meta box fields are normally updated like this:

  function fredningszone_meta_box() {

    add_meta_box( 
        'punkt_fredningszone', // $id - Meta box ID (used in the 'id' attribute for the meta box).
        'Data for fredningszone', // $title - Title of the meta box.
        'punkt_fredningszone_callback', // $callback - Function that fills the box with the desired content. The function should echo its output. 
        'punkt', // $screen - he screen or screens on which to show the box (such as a post type, 'link', or 'comment'). 
        'normal', // $context - The context within the screen where the boxes should display.
        'high' // $priority - The priority within the context where the boxes should show ('high', 'low').
    );
}

add_action( 'add_meta_boxes', 'fredningszone_meta_box' );

/**
 * Enable and display custom fields.
**/

function punkt_fredningszone_callback() { 

    global $post;  

    $meta = get_post_meta( $post->ID, 'fredningszone_data', true ); ?>

    <input type="hidden" name="fredningszone_data_nonce" value="<?php echo wp_create_nonce( basename(__FILE__) ); ?>">

    <!-- All fields goes below this line -->

    <p>
        <label for="fredningszone_data[id]">ID</label>
        <br>
        <input type="text" name="fredningszone_data[id]" id="fredningszone_data[id]" class="regular-text widefat" placeholder="Indtast fredningszonens ID (f.eks 450)" value="<?php echo $meta['id']; ?>">
    </p>

..but when i parse data from the CSV via another funtion, that I build, I cannot access the fields of the meta box. See code below:

Following code is a snippet from the import plugin, that I am trying to build, where the CSV data won't parse to fields of meta box. See below:

$check_post_exists = function( $title ) use ( $wpdb, $postTypeArray ) {

        // Get an array of all posts within our custom post type
        $posts = $wpdb->get_col( "SELECT post_title FROM {$wpdb->posts} WHERE post_type = '{$postTypeArray["custom-post-type"]}' AND post_status = 'publish'" );

        // Check if the passed title exists in array
        return in_array( $title, $posts );
    };

    $i = 0;

    foreach ( $posts() as $post ) {

        // If the post exists, skip this post and go to the next one
        if ( $check_post_exists( $post["zoneid"] ) ) {
            continue;
        }

        $i++;

        // Insert the post into the database
        $post["id"] = wp_insert_post( array(
            "post_title" => $post["zoneid"],
            "post_content" => $post["bemaerkning"],
            "post_type" => $postTypeArray["custom-post-type"],
            "post_punktcat" => array( 4 ),
            "post_status" => "publish"
        ));

        // Set post category to 4
        wp_set_post_terms($post["id"], 4, 'punktcat', false ); 

        $meta = get_post_meta($post["id"], 'fredningszone_data', true );

        var_dump($meta);

        // THIS IS THE FIELD I WANT TO UPDATE, BUT I HAVE NOT YET SUCCESFULLY POPULATED THE FIELD YET
        update_post_meta($post["id"], $meta["id"], $post["zoneid"]);

        // Update Custom Meta
        update_post_meta($post["id"], '_location', $post["zoneid"]);
    }

    echo '<div id="message" class="updated fade"><p>' . $i . ' posts have succesfully been imported from CSV!' . '</p></div>';

How can I parse data into field of custom meta box?

Answer 1

Okay. I solved the problem myself. I was not populating the the array of a meta_key the correct way.

Below, you will find a working solution:

$check_post_exists = function( $title ) use ( $wpdb, $postTypeArray ) {

        // Get an array of all posts within our custom post type
        $posts = $wpdb->get_col( "SELECT post_title FROM {$wpdb->posts} WHERE post_type = '{$postTypeArray["custom-post-type"]}' AND post_status = 'publish'" );

        // Check if the passed title exists in array
        return in_array( $title, $posts );
    };

    $i = 0;
    $e = 0;

    foreach ( $posts() as $post ) {

        // If the post exists, skip this post and go to the next one
        if ( $check_post_exists( $post["properties/ID"] ) ) {
            $e++;
            continue;
        }

        $i++;

        // Insert the post into the database
        $post["id"] = wp_insert_post( array(
            "post_title" => $post["properties/ID"],
            "post_type" => $postTypeArray["custom-post-type"],
            "post_punktcat" => array( 4 ),
            "post_status" => "publish"
        ));

        // Set post category to 4
        wp_set_post_terms($post["id"], 4, 'punktcat', false ); 

        $meta = get_post_meta( $post["id"], 'fredningszone_data', true );

        $fredningszone_data = array(
            "id" => $post["properties/ID"],
            "navn" => $post["properties/NAVN"], 
            "kontaktsted" => $post["properties/Kontaktsted"],
            "fredningsperiode" => $post["properties/FREDNINGSP"],
            "periode_type" => $post["properties/PeriodeType"], 
            "lovgivningsgrundlag" => $post["properties/LOVGRUNDLA"],
            "bemaerkning" => $post["properties/BEMARKNING"],
            "www" => $post["properties/WWW"],
            "www2" => $post["properties/WWW2"],
            "geometry" => $post["geometry/type"]
        );

        // Update meta box values
        update_post_meta($post["id"], 'fredningszone_data', $fredningszone_data);
        //update_post_meta($post["id"], 'fredningszone_data', $post["zoneid"]);
        update_post_meta($post["id"], '_location', $post["zoneid"]);
    }