_buildKeyStrokeId(keyCode, options) {
    let keyStrokeId = `${keyCode}`;
    if (options && typeof options === 'object') {
      if (options.ctrl !== 'undefined' && options.ctrl) {
        keyStrokeId += '^';
      }
      if (options.shift !== 'undefined' && options.shift) {
        keyStrokeId += '+';
      }
      if (options.alt !== 'undefined' && options.alt) {
        keyStrokeId += '!';
      }
    }
    return keyStrokeId;
  }
/**
   * Builds a unique string id for a key
   * with an optional options object
   *
   * @param {Integer} keyCode
   *          the key
   * @param {object} [options]
   *          an optional object with key modifiers
   * @returns {string}
   *          a unique string identifying this key stroke
   */
Builds a unique string id for a key
with an optional options object

@param {Integer} keyCode
the key
@param {object} [options]
an optional object with key modifiers
@returns {string}
a unique string identifying this key stroke
Builds a unique string id for a key with an optional options object @param { Integer } keyCode the key @param { object } [ options ] an optional object with key modifiers @returns { string } a unique string identifying this key stroke
_buildKeyStrokeId(keyCode, options) {
    let keyStrokeId = `${keyCode}`;
    if (options && typeof options === 'object') {
      if (options.ctrl !== 'undefined' && options.ctrl) {
        keyStrokeId += '^';
      }
      if (options.shift !== 'undefined' && options.shift) {
        keyStrokeId += '+';
      }
      if (options.alt !== 'undefined' && options.alt) {
        keyStrokeId += '!';
      }
    }
    return keyStrokeId;
  }
_buildKeyStrokeId ( keyCode , options ) { let keyStrokeId = ` ${ keyCode } ` ; if ( options && typeof options === 'object' ) { if ( options . ctrl !== 'undefined' && options . ctrl ) { keyStrokeId += '^' ; } if ( options . shift !== 'undefined' && options . shift ) { keyStrokeId += '+' ; } if ( options . alt !== 'undefined' && options . alt ) { keyStrokeId += '!' ; } } return keyStrokeId ; }
Builds a unique string id for a key
 with an optional options object
Builds a unique string id for a key with an optional options object