🍇Basic React Part 2 - on 으로 시작하는 이벤트 연습(1)

import React, { Component } from 'react'

class EventPractice extends Component {
  constructor(props) {
    super(props)
    this.state = {
      message: '',
    }
  }
  render() {
    return (
      <div>
        <h1>내인생의 이벤트는 언제오나</h1>
        <input
          id="msg"
          type="text"
          name="message"
          value={this.state.message}
          placeholder="새해소망을입력하세요"
          onChange={e => this.setState({ message: e.target.value })}
        />
        <button
          onClick={() => {
            alert(this.state.message)
            document.querySelector('#msg').value = ''
            this.setState({ message: '' })
          }}
        >
          확인
        </button>
      </div>
    )
  }
}

export default EventPractice

import React, { Component } from 'react'

class EventPractice extends Component {
  constructor(props) {
    super(props)
    this.state = {
      message: '',
    }
    this.handleChange = this.handleChange.bind(this)
    this.handleClick = this.handleClick.bind(this)
  }
  handleChange(event) {
    this.setState({
      message: event.target.value,
    })
  }

  handleClick() {
    alert(this.state.message)
    document.querySelector('#msg').value = ''
    this.setState({
      message: '',
    })
  }
  render() {
    return (
      <div>
        <h1>내인생의 이벤트는 언제오나</h1>
        <input
          id="msg"
          type="text"
          name="message"
          value={this.state.message}
          placeholder="새해소망을입력하세요"
          onChange={this.handleChange}
        />
        <button onClick={this.handleClick}>확인</button>
      </div>
    )
  }
}

export default EventPractice

handleChange = event => {
  this.setState({
    message: event.target.value,
  })
}

handleClick = () => {
  alert(this.state.message)
  document.querySelector('#msg').value = ''
  this.setState({
    message: '',
  })
}