我正在开发一个小应用程序,在该程序中,我为两个不同的人在输入金额后显示他们的余额。例如,如果Alex的当前余额是100,我在收入字段中输入一个数字,则余额增加。当您在支出字段中输入一个数字时,余额减少。第二个人也是如此。我尝试在按下回车键后清除字段。
App.tsx
import React, { useState } from 'react'
import './App.css'
import { Header } from './components/Header'
import { Balance } from './components/Balance'
function App() {
const [alexBalance, setAlexBalance] = useState(0)
const [yuliaBalance, setYuliaBalance] = useState(0)
const [value, setValue] = useState('')
const handleChange = (e: React.ChangeEvent<HTMLInputElement>) => {
setValue(e.target.value)
}
const handleKeyDown = (e: React.KeyboardEvent) => {
if (e.key === 'Enter') {
calcResult(e.currentTarget.id, value)
// document.querySelectorAll('input').forEach(input => (input.value = ''))
}
}
const calcResult = (id: string, val: string) => {
switch (id) {
case 'deposit-Alexander':
setAlexBalance(alexBalance + Number(val))
break
case 'withdraw-Alexander':
setAlexBalance(alexBalance - Number(val))
break
case 'deposit-Yulia':
setYuliaBalance(yuliaBalance + Number(val))
break
case 'withdraw-Yulia':
setYuliaBalance(yuliaBalance - Number(val))
break
}
}
return (
<div className='App'>
<Header />
<div className='wrapper flex flex-wrap justify-around'>
<Balance user='Alexander' onChange={handleChange} onKeyDown={handleKeyDown} balance={alexBalance}
/>
<Balance user='Yulia' onChange={handleChange} onKeyDown={handleKeyDown} balance={yuliaBalance}
/>
</div>
</div>
)
}
export default App
Balance.tsx
import { Input } from './Input'
import React from 'react'
type BalanceProps = {
user: string
balance: any
onKeyDown: React.KeyboardEventHandler
onChange: React.ChangeEventHandler<HTMLInputElement>
}
export const Balance = (props: BalanceProps) => {
return (
<div className='balance mb-8 mt-8 border-2 shadow rounded py-8 px-8 w-4/6 max-w-3xl'>
<div className='balance__header flex flex-col'>
<span className=''>
{props.user}'s current balance: {props.balance}
</span>
<span>Enter a value</span>
<Input
id={`deposit-${props.user}`}
name={`add-${props.user}`}
placeholder='+ income'
onKeyDown={props.onKeyDown}
onChange={props.onChange}
/>
<Input
id={`withdraw-${props.user}`}
name={`sub-${props.user}`}
placeholder='- expense'
onKeyDown={props.onKeyDown}
onChange={props.onChange}
/>
</div>
</div>
)
}
Input.tsx
import { ChangeEventHandler, KeyboardEventHandler } from 'react'
type InputProps = {
placeholder: string
id: string
name: string
onKeyDown: KeyboardEventHandler<HTMLInputElement>
onChange: ChangeEventHandler
}
export const Input = (props: InputProps) => {
return (
<div>
<input
type='text'
id={props.id}
name={props.name}
className='input shadow appearance-none border rounded w-full py-2 px-3 text-gray-700 leading-tight focus:outline-none focus:shadow-outline text-center w-4/6 mt-2 mb-2'
onKeyDown={props.onKeyDown}
onChange={props.onChange}
placeholder={props.placeholder}
/>
</div>
)
}
我试过这个...
const handleKeyDown = (e: React.KeyboardEvent) => {
if (e.key === 'Enter') {
calcResult(e.currentTarget.id, value)
document.querySelectorAll('input').forEach(input => (input.value = ''))
}
}
这对我很有效,但是,正如我所知,这不是最佳实践。我希望得到一个使用状态的解决方案。我不希望为每个输入使用单独的状态。非常感谢
1条答案
按热度按时间vc6uscn91#
你只要在点击回车键时将状态设置为空就可以了,所以不要在e.key==='Enter'块中添加注解代码,而是将你想要的状态设置为空。