var parentId = 96; // the post id
var metaData = new wp.api.collections.PostMeta(\'\', {parent: parentId});
metaData.fetch()
  .done(function(data) {
    var someKey = data.findWhere({key: \'someKey\'});
    someKey.set(\'value\', \'newValue\');

    someKey.save({parent: parentId});
  });

现在，您还可以使用models api：

var post = new wp.api.models.Post( { id: 1 } );
post.fetch();
post.setMeta(\'metaKey\', \'metaValue\');
// Or multiple metas at one time:
post.setMetas({metaKeyOne: \'metaValueOne\', metaKeyTwo: \'metaValueTwo\'});
post.save()

add_action(
    \'init\',
    function() {
        register_post_meta(\'my_post_type\', \'my_meta_key\', [\'show_in_rest\' => true, \'single\' => true]);
    }
);