4.2.3.1 기본 방식

EventPractice.js

import React, { Component } from 'react';
 
class EventPractice extends Component {
 
  state = {
    message: ''
  }
 
  constructor(props) {
    super(props);
    this.handleChange = this.handleChange.bind(this);
    this.handleClick = this.handleClick.bind(this);
  }
 
  handleChange(e) {
    this.setState({
      message: e.target.value
    });
  }
 
  handleClick() {
    alert(this.state.message);
    this.setState({
      message: ''
    });
  }
 
  render() {
    return (
      <div>
        <h1>이벤트 연습</h1>
        <input
          type="text"
          name="message"
          placeholder="아무거나 입력해 보세요"
          value={this.state.message}
          onChange={this.handleChange}
        />
        <button onClick={this.handleClick}>확인</button>
      </div>
    );
  }
}
 
export default EventPractice;

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