我想通过ajax从前端保存/更新自定义用户元字段。此字段应包含帖子ID列表。不允许使用双重ID。

我的问题是，每次更新字段值时，它都会被保存为多维数组。

例如，保存的数据如下所示：

Array ( [0] => Array ( [0] => Array ( [0] => [1] => 70 [2] => 79 ) [1] => 79 ) [1] => 93 )

我尝试了不同的方法$single 的参数get_user_meta(), 似乎这就是问题所在。但我没能找到解决办法。

我想问题是我得到的值的格式get_user_meta().

在我的排队函数中，我使用wp_localize_script 向自定义JS文件添加值。在这里，我想检查是否已经保存了一个值，并将该值发送到JS文件。

（我在代码中添加了注释）

function my_custom_enqueue() {
    if ( is_user_logged_in() ) {

        wp_enqueue_script( \'ajax-script\', plugins_url(\'ajax.js\', __FILE__), array(\'jquery\') );

        $current_user = wp_get_current_user();
        $saved_ids = get_user_meta($current_user->ID, \'postlist\', false); 
        // if changed to true, jquery is not working anymore, but if true it can also be an array

        // do something if $saved_ids is empty ?! check if it is an array?!

        wp_localize_script( \'ajax-script\', \'my_ajax_object\', array( 
            \'ajax_url\' => admin_url( \'admin-ajax.php\' ),
            \'saved_ids\' => $saved_ids,
        ) );
    }
}
add_action( \'wp_enqueue_scripts\', \'my_custom_enqueue\' );

jQuery(document).ready(function($){

    //get the $saved_ids value
    var postIdsToCompare = my_ajax_object.saved_ids;

    $(document).on(\'click\', \'.add-to-list\', function(e) {
        e.preventDefault();  

        // get post id from data-id of element
        var idToAdd = $(this).attr(\'data-id\');          

        // see if post id already exists in postIdsToCompare
        // this is not working anymore because of the multidimension arrays
        var found = $.inArray(idToAdd, postIdsToCompare);

        if (found >= 0) {
            // Element was found, remove it from array
            postIdsToCompare.splice(found, 1);
        } else {
            // Element was not found, add it to array
            postIdsToCompare.push(idToAdd);
        }

        var data = {
            \'action\': \'make_post_list\', // name of php function "wp_ajax_make_post_list"
            \'ids_to_compare\': postIdsToCompare, // to use $_POST[\'ids_to_compare\']
        };

        $.post(my_ajax_object.ajax_url, data, function(response) {
            alert(\'Added\');
        });
    });
});

add_action( \'wp_ajax_make_post_list\', \'make_post_list_callback\' );
function make_post_list_callback() {

    global $wpdb; // this is how you get access to the database

    // Ensure we have the data we need to continue
    if( ! isset( $_POST ) || empty( $_POST ) || ! is_user_logged_in() ) {
        exit;
    }

    $user_id = get_current_user_id();

    $saved_ids = get_user_meta($user_id, \'postlist\', true);

    $ids_to_compare = $_POST[\'ids_to_compare\'];

    //save user meta here
    update_user_meta(
        $user_id, // user id
        \'postlist\', // meta key
        $ids_to_compare, // meta value
        $saved_ids // prev value, tried without it also
    );

    wp_die();
}