详解三种方式在React中解决绑定this的作用域问题并传参

import React from 'react';

export default class BindWithThis extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      msg:"BindWithThis"
    }
  }

  render() { 
    return <div>
      <input type="button" value="Way1" onClick={this.changeMsg1}/>
      <hr/>
      <h3>{this.state.msg}</h3>
    </div>
  }

  changeMsg1(){
    console.log(this)
    this.setState({
      msg:"Way1"
    })
  }
}

render() { 
    return <div>
      <input type="button" value="Way1" onClick={this.changeMsg1.bind(this)}/>
      <hr/>
      <h3>{this.state.msg}</h3>
    </div>
  }

render() { 
  return <div>
    <input type="button" value="Way1" onClick={this.changeMsg1.bind(this,"壹","贰")}/>
    <hr/>
    <h3>{this.state.msg}</h3>
  </div>
}

changeMsg1(arg1,arg2){
  this.setState({
    msg:"Way1"+arg1+arg2
  })
}

import React from 'react';

export default class BindWithThis extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      msg:"BindWithThis"
    }

    // 当为一个函数调用bind 改变this的指向之后 bind函数的返回值是这个被改变this指向的函数的改变后的引用 因此需要重新接收
    this.changeMsg2 = this.changeMsg2.bind(this,"壹","贰")
  }

  render() { 
    return <div>
      <input type="button" value="Way2" onClick={this.changeMsg2}/>
      <hr/>
      <h3>{this.state.msg}</h3>
    </div>
  }

  changeMsg2(arg1,arg2){
    this.setState({
      msg:"Way2"+arg1+arg2
    })
  }
}

render() { 
  return <div>
    <input type="button" value="Way3" onClick={() => {this.changeMsg3("壹","贰")}}/>
    <hr/>
    <h3>{this.state.msg}</h3>
  </div>
}

changeMsg3 = (arg1,arg2) => {
  this.setState({
    msg:"Way3"+arg1+arg2
  })
}