WP_Customize_Upload_Control

17class WP_Customize_Upload_Control extends WP_Customize_Media_Control {18	/**19	 * Control type.20	 *21	 * @since 3.4.022	 * @var string23	 */24	public $type = 'upload';25 26	/**27	 * Media control mime type.28	 *29	 * @since 4.1.030	 * @var string31	 */32	public $mime_type = '';33 34	/**35	 * Button labels.36	 *37	 * @since 4.1.038	 * @var array39	 */40	public $button_labels = array();41 42	public $removed = '';         // Unused.43	public $context;              // Unused.44	public $extensions = array(); // Unused.45 46	/**47	 * Refresh the parameters passed to the JavaScript via JSON.48	 *49	 * @since 3.4.050	 *51	 * @uses WP_Customize_Media_Control::to_json()52	 */53	public function to_json() {54		parent::to_json();55 56		$value = $this->value();57		if ( $value ) {58			// Get the attachment model for the existing file.59			$attachment_id = attachment_url_to_postid( $value );60			if ( $attachment_id ) {61				$this->json['attachment'] = wp_prepare_attachment_for_js( $attachment_id );62			}63		}64	}65}