React十进制和二进制转换的实现和分析

【描述】

模仿官方文档的摄氏度和华氏度的转换，实现十进制和二进制的互换。

【实现】

import React from 'react';
import ReactDOM from 'react-dom';

function Convert(value,setWhat){
    if(value===''){return ''}
    if(setWhat==='setDec'){
        return parseInt(value,2);
    }else{
        return parseInt(value).toString(2);
    }
}

class InputBox extends React.Component{
    constructor(props){
        super(props);
        this.handleChange=this.handleChange.bind(this);
    }
    handleChange(e){
        //数据流向：子->父。onChange事件接受父组件的回调函数，实现把event.target.value传到父组件
        this.props.callBack(e.target.value); 
    }
    render(){
        return(
            <div>
                <p>Input: {this.props.title}</p>
                <input value={this.props.selfValue} onChange={this.handleChange} />
            </div>
        )
    }
}

class Main extends React.Component{
    constructor(props){
        super(props);
        this.callBack_changeDec=this.callBack_changeDec.bind(this);
        this.callBack_changeBin=this.callBack_changeBin.bind(this);
        this.state={
            wanted:'wantDec',
            result:'',
        }
    }
    callBack_changeDec(inputValue){
        this.setState({result:inputValue});
        this.setState({wanted:'wantBin'});
    }
    callBack_changeBin(inputValue){
        this.setState({result:inputValue});
        this.setState({wanted:'wantDec'});
    }
    
    render(){
        var result_titleIsDec=this.state.wanted==='wantBin'?this.state.result:Convert(this.state.result,'setDec');
        var result_titleIsBin=this.state.wanted==='wantBin'?Convert(this.state.result,'setBin'):this.state.result;
        return(
            <div>
                <InputBox title='Dec' callBack={this.callBack_changeDec} selfValue={result_titleIsDec}/>
                <InputBox title='Bin' callBack={this.callBack_changeBin} selfValue={result_titleIsBin}/>
            </div>
        )
    }
}
ReactDOM.render(<Main />, document.getElementById('root'));

【解析】