export declare class FileHelper {
    /**
     * use the file reader to read a file
     *
     * return it as array buffer
     *
     * @param file
     * @private
     */
    static fileParse(file: Blob): Promise<ArrayBuffer>;
    /**
     * use the file reader to read a file
     *
     * return it as url string
     *
     * @param file
     * @param asUrl
     * @private
     */
    static fileParse(file: Blob, asUrl: boolean): Promise<string>;
}