javascript - 当我单击按钮每个按钮(如数组)时如何显示 setstate 值？

Question

class ToggleClick extends React.Component{
    constructor(props){
        super(props)
        this.state = {
            changeText :  "Welcome Zeeshan",    
            changeText1 : "Hello Zeeshan",  
            changeText2 : "Hello World" 
        }           
        this.handleClick = this.handleClick.bind(this); 
    }
    handleClick = (e) => {
        e.preventDefault();
    const id = e.target.id;
    //alert(id);
    this.setState({ changeText: 'Hello Zeeshan' , changeText1 : "Hello Zeeshan 1" , changeText2 : "Hello Zeeshan 3" })
    } 

    render(){
        return(
            <div>
            <h2>Bind Event</h2>
                    <button id="btn1" onClick={this.handleClick}>Click</button>
                    <h4>{this.state.changeText}</h4>
            </div>
        );
    }
}

export default ToggleClick;

Answer 1

setState 是异步的。所以使用回调。

this.setState({
  changeText: 'Hello Zeeshan' 
}, ()=>console.log(this.state.changeText))