ValidationSample.js

import React, { Component } from 'react';
import './ValidationSample.css';
 
class ValidationSample extends Component {
  state = {
    password: '',
    clicked: false,
    validated: false
  }
 
  handleChange = (e) => {
    this.setState({
      password: e.target.value
    });
  }
 
  handleButtonClick => () => {
    this.setState({
      clicked: true,
      validated: this.state.password === '0000'
    })
  }
 
  render() {
    return (
      <div>
        <input
          type="password"
          value={this.state.password}
          onChange={this.handleChange}
          className={this.state.clicked ? (this.state.validated ? 'success' : 'failure') : ''}
        />
        <button onClick={this.handleButtonClick}>검증하기</button>
      </div>
    );
  }
}
 
export default ValidationSample;

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