text: export default {
      queryNodeById: function (id, node) {  // 判断是否有子节点时用到该方法
          if (node.id === id) {
              return node;
          }
          let children = node.children, result;
          if (children && children.length > 0) {
              for (let i = 0; i < children.length; i++) {
                  result = this.queryNodeById(id, children[i]);
                  if (result) {
                      return result;
                  }
              }
          }
          return null;
      }
  }