权限示例界面：

代码如下

<el-tree
    ref="refTree"
    :data="prdList"
    :props="{label:'name',children: 'childrenList'}"
    show-checkbox
    default-expand-all
    node-key="id"
    :default-checked-keys="[5,22]"    
    @check-change="permissionClick"
  ></el-tree>

 数据：

prdList: [{
          id: 1,
          name: '(示例)一级 1',
          childrenList: [{
            id: 4,
            name: '二级 1-1',
            childrenList: [{
              id: 9,
              name: '三级 1-1-1'
            }, {
              id: 10,
              name: '三级 1-1-2',
              childrenList: [
                { id: 22, name: '四级 1-1-1' },
                { id: 23, name: '四级 1-1-2' },
                { id: 24, name: '四级 1-1-3' },
              ]
            }]
          }]
        }, {
          id: 2,
          name: '管理员',
          childrenList: [{
            id: 5,
            name: '董事长'
          }, {
            id: 6,
            name: '经理'
          }]
        }, {
          id: 3,
          name: '普通员工',          
        }]

:props="{label:'permissionDesc'}"  显示的字段是数据里的permissionDesc

默认选中：:default-checked-keys="[5,22]"  对应选中的是id为5和22