javascript - 如何在 react 中单击按钮时获取输入字段值？

Question

你能告诉我如何在点击按钮时获取输入字段值吗，我正在使用 react 钩子(Hook)。我想获取 first name 和 lastname 值按钮点击。我已经在我的函数组件中传递了 name 属性。

这是我的 code

import React, { Component, useState } from 'react';
import { render } from 'react-dom';

export default function InputField({name,label}) {
  const [state, setState] = useState('')
  return (
    <div>
     <label>{label}</label>
      <input type="text" 
      value={state} 
      name={name}
      onChange={(e) => setState(e.target.value)} />

      {state}
    </div>
  );

}

Answer 1

Use <form> tag with useRef hook

包装你的 <InputField>带有 html <form> 的标签标记并使用react ref在以后。像这样:

import React, { Component, useRef } from 'react'
import { render } from 'react-dom'

import InputField from './inputfield'

import './style.css'

function App () {
  const nameForm = useRef(null)

  const handleClickEvent = () => {
     const form = nameForm.current
     alert(`${form['firstname'].value} ${form['lastname'].value}`)
  }

  return (
    <div>
      <form ref={nameForm}>
       <InputField label={'first name'} name={'firstname'}/>
       <InputField label={'last name'} name={'lastname'}/>
      </form>
      <button onClick={handleClickEvent}>gett value</button>
    </div>
  )
}

render(<App />, document.getElementById('root'))

工作示例: https://stackblitz.com/edit/react-shtnxj