    /**
     * fabric鼠标事件枚举
     * @readonly
     * @private
     */
    const fbMouseEventType = Object.freeze({
      mouseDown: 'mouse:down',
      mouseUp: 'mouse:up',
      mouseMove: 'mouse:move',
      doubleClick: 'mouse:dblclick',
      /**
       * 鼠标滚轮事件
       */
      zoom: 'mouse:wheel',
      /**
       * 鼠标移出事件
       */
      mouseover: 'mouse:over',
      /**
       * 鼠标移入事件
       */
      mouseout: 'mouse:out'
    })
    export default fbMouseEventType