element,el-tree节点全部展开|关闭_eltree关闭所有展开

    
 
    checkChange(flag) { // 点击切换状态、展开|收起
      this.isUnfold({ data: this.data, flag })
    },
    isUnfold({ data, flag }) { // 全部展开or收起
      const that = this
      data.forEach((el) => {
        that.$refs.tree[0].store.nodesMap[el.id].expanded = flag
        if (el.children && el.children.length > 0) {
          that.isUnfold({ data: el.children, flag })
        }
      })
    },

    <el-checkbox
      v-model="checked"@change="checkChange">
        全部展开|收起
    </el-checkbox>