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Javascript 如何显示设置状态值时,我点击每个按钮像数组? 类切换单击扩展反应组件{ 建造师(道具){ 超级(道具) 此.state={ changeText:“欢迎泽山”, changeText1:“你好,泽山”, changeText2:“你好,世界” } this.handleClick=this.handleClick.bind(this); } handleClick=(e)=>{ e、 预防默认值(); const id=e.target.id; //警报(id); this.setState({changeText:'Hello Zeeshan',changeText1:'Hello Zeeshan 1',changeText2:'Hello Zeeshan 3'}) } render(){ 返回( 绑定事件 点击 {this.state.changeText} ); } } 导出默认切换点击;_Javascript_Reactjs - Fatal编程技术网

Javascript 如何显示设置状态值时,我点击每个按钮像数组? 类切换单击扩展反应组件{ 建造师(道具){ 超级(道具) 此.state={ changeText:“欢迎泽山”, changeText1:“你好,泽山”, changeText2:“你好,世界” } this.handleClick=this.handleClick.bind(this); } handleClick=(e)=>{ e、 预防默认值(); const id=e.target.id; //警报(id); this.setState({changeText:'Hello Zeeshan',changeText1:'Hello Zeeshan 1',changeText2:'Hello Zeeshan 3'}) } render(){ 返回( 绑定事件 点击 {this.state.changeText} ); } } 导出默认切换点击;

Javascript 如何显示设置状态值时,我点击每个按钮像数组? 类切换单击扩展反应组件{ 建造师(道具){ 超级(道具) 此.state={ changeText:“欢迎泽山”, changeText1:“你好,泽山”, changeText2:“你好,世界” } this.handleClick=this.handleClick.bind(this); } handleClick=(e)=>{ e、 预防默认值(); const id=e.target.id; //警报(id); this.setState({changeText:'Hello Zeeshan',changeText1:'Hello Zeeshan 1',changeText2:'Hello Zeeshan 3'}) } render(){ 返回( 绑定事件 点击 {this.state.changeText} ); } } 导出默认切换点击;,javascript,reactjs,Javascript,Reactjs,设置状态是异步的。所以使用回调 class ToggleClick extends React.Component{ constructor(props){ super(props) this.state = { changeText : "Welcome Zeeshan", changeText1 : "Hello Zeeshan", changeText2 : "He

设置状态是异步的。所以使用回调

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;

setState是异步的。所以使用回调

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;

我不知道你的意思,但如果你想在每次点击时更改文本,你可以这样做:

class-ToggleButton扩展了React.Component{
构造函数(…道具){
超级(…道具)
此.state={
文本索引:0,
文本:[
“你好,泽山1号”,
“你好,泽山2号”,
“你好,泽山3号”
]
};
}
rotateText(){
const{text,textIndex}=this.state;
这是我的国家({
textIndex:textIndex{text[textIndex]}
);
}

}
我不知道你的意思,但是如果你想在每次点击时更改文本,你可以这样做:

class-ToggleButton扩展了React.Component{
构造函数(…道具){
超级(…道具)
此.state={
文本索引:0,
文本:[
“你好,泽山1号”,
“你好,泽山2号”,
“你好,泽山3号”
]
};
}
rotateText(){
const{text,textIndex}=this.state;
这是我的国家({
textIndex:textIndex{text[textIndex]}
);
}

}
记住setState是异步的,假设您的状态为(在构造函数中)

设置状态的sintax为:

this.state = {
   field1: value1, 
   field2: value 2
}
使用setState并在任何事件上访问当前状态的适当方法是使用第一个参数作为更新程序函数,如下所示(不需要使用第二个参数):

返回的值是所需的新状态。在您的特定情况下,它类似于构造函数:

this.setState( (state) => {
   return {
    field1: somefunction(state)      // eg. state.field1 + state.field2
    field2: someOtherfunction(state) // eg. state.field2 + 1
   }
});
在点击事件中,你会

this.state = { 
 changeText: "Hello Zeeshan"
}

记住setState是异步的,假设您的状态为(在构造函数中)

设置状态的sintax为:

this.state = {
   field1: value1, 
   field2: value 2
}
使用setState并在任何事件上访问当前状态的适当方法是使用第一个参数作为更新程序函数,如下所示(不需要使用第二个参数):

返回的值是所需的新状态。在您的特定情况下,它类似于构造函数:

this.setState( (state) => {
   return {
    field1: somefunction(state)      // eg. state.field1 + state.field2
    field2: someOtherfunction(state) // eg. state.field2 + 1
   }
});
在点击事件中,你会

this.state = { 
 changeText: "Hello Zeeshan"
}