GBS: Upload and Set Attachment

function.php

	
	/**
	 * Add a file as a post attachment.
	 *
	 * @return null 
	 */
	public static function set_attachement( $post_id, $files ) {
		if (!function_exists('wp_generate_attachment_metadata')){
			require_once(ABSPATH . 'wp-admin' . '/includes/image.php');
			require_once(ABSPATH . 'wp-admin' . '/includes/file.php');
			require_once(ABSPATH . 'wp-admin' . '/includes/media.php');
		}
		foreach ($files as $file => $array) {
			if ($files[$file]['error'] !== UPLOAD_ERR_OK) {
				self::set_message('upload error : ' . $files[$file]['error']);
			}
			$attach_id = media_handle_upload( $file, $post_id );
		}
		// Make it a thumbnail while we're at it.
		if ($attach_id > 0){
			update_post_meta($post_id,'_thumbnail_id',$attach_id);
		}
		return $attach_id;
	}