问题:
如果值未更改,如何防止提交?我尝试使用useState
执行此操作。
Snippet:
import React from 'react'
import {Formik, Form, Field} from 'formik'
const Search = () => {
const [searchValue, setSearchValue] = useState('')
const handleSubmit = q => {
window.location.href = `https://for-example.com/search?q=${q}`
}
return (
<Formik onSubmit={({q}, {setSubmitting}) => {
setSubmitting(false)
setSearchValue(q) // <===
return q !== searchValue && handleSubmit(q) // <===
}} initialValues={{q: ''}} render={() => (
<Form>
<Field name='q' />
</Form>
)}/>
)
}
P.S。此方法有效,但我认为不值得为此简单任务创建useState
。我可以用其他方式检查搜索值吗?
如果您要在handleSubmit
功能中更改窗口位置,则无需担心将来的状态。您可以使用在渲染prop中传递的dirty
prop,如下所示:
import React from 'react'
import {Formik, Form, Field} from 'formik'
const Search = () => {
const handleSubmit = q => {
window.location.href = `https://for-example.com/search?q=${q}`
}
return (
<Formik onSubmit={({q}, {setSubmitting}) => {
setSubmitting(false)
handleSubmit(q)
}} initialValues={{q: ''}} render={({ dirty, handleSubmit, isSubmitting }) => (
<form onSubmit={handleSubmit}>
<Field name='q' />
<button type="submit" disabled={!dirty || isSubmitting}>
Submit
</button>
</form>
)}/>
)
}
[如果您不更改提交时的位置,或者出于任何其他原因,同一表格可以多次提交(具有不同的值),则您需要某种形式的state
,无论是本地的还是本地的。
希望有帮助。