text: /**
   *
   * @param {Array} treeList 树形列表
   * @param {Function} fn  处理函数
   * @param {String} [childrenKey='children'] 子级key
   * @returns {Array}
   */
  export default function (treeList, fn, childrenKey = 'children') {
    c(treeList, null)
    function c(list, parent) {
      _.forEach(list, (item, index) => {
        if (item[childrenKey]) c(item[childrenKey], item)
        if (_.isFunction(fn)) {
          fn(item, parent, index)
        }
      })
    }
  
    return treeList
  }
  