javascript - react 渲染错误

Question

当我尝试呈现我的嵌套导航时收到此错误:

Objects are not valid as a React child (found: object with keys {id, name}). If you meant to render a collection of children, use an array instead.

我不确定如何正确渲染我的映射导航。任何帮助将不胜感激。

let items = [
  { id: 0, name: 'Products', items: [{ id: 2, name: 'M-PET.NET' }, { id: 3, name: 'M-PET.WEB' }]},
  { id: 4, name: 'Services', items: [{ id: 5, name: 'M-PET Hosted' }, { id: 6, name: 'Custom Programming' }]},
  { id: 7, name: 'TurnKey', items: [{ id: 8, name: 'About' }, { id: 9, name: 'Project Management' }, { id: 10, name: 'IT Tasks' }, { id: 11, name: 'Maintenance' }]},
  { id: 12, name: 'Key Industries', items: [{ id: 13, name: 'Transportation' }, { id: 14, name: 'Hospitality' }]},
  { id: 15, name: 'Company', items: ['Team', 'History']},
]

class Nav extends Component {
  render() {
    let nav = items.map((item) => <li node={item} children={item.items} key={item.id}></li>)
    console.log(nav)
    return (
      <div>
        <ul className='nav'>
          {nav}
        </ul>
      </div>
    )
  }
}

export default Nav

Answer 1

将项目放入状态

state = {
 items : [...] //array
}

然后将其映射为

let nav = this.state.items...

或者，如果您不将其置于状态，则可以使用 context

访问它

let nav = this.items...

这里要注意的一点是在同一个类中使用 items，在你的例子中是 Nav，方法是导入源代码或在同一个类中定义它。

class Nav extends Component {

 let items = [...];
 ...
 render(){
  let nav = this.items...
 }
}

或

class Nav extends Component {

 state = { items:[...] };
 ...
 render(){
  let nav = this.state.items...
 }
}