初始组件的状态由 useState 更改为 true

Question

在我的 class 组件中想要将 Initial State 更改为 True 但不想在 true 之后更改为 false，只需更改为 true，如何更改 setState？感谢您的帮助。

class Cardlist extends Component {
state = {
    setopen : false
  }
  setOpen = () => this.setState(prevState => ({
    setopen : !prevState.setopen  // I don't know how can changed setState to always true
  }))
render() {
  const { products } = this.props;

return (
  <div>
       <button onClick={() => this.setOpen(true)} className="font-medium">
        Basket
       </button>
       {(this.state.setopen) ? <Card {...products} open={this.state.setopen} /> : ''}
  </div>  
    )
  }
}

Answer 1

始终保持 setOpen 中的状态为真。

setOpen = () => this.setState(prevState => ({setopen : true})
...
  <div>
       <button onClick={this.setOpen} className="font-medium">
        Basket
       </button>
  </div>

根据传递的参数制作状态

  setOpen = (newVal) => this.setState({setopen : newVal})
...
  <div>
       <button onClick={() => this.setOpen(true)} className="font-medium">
        Basket
       </button>
       <button onClick={() => this.setOpen(false)} className="font-medium">
        Basket
       </button>
  </div>

初始组件的状态由 useState 更改为 true

State of a Initial Component By useState Change to true

state

reactjs

use-state