React hook form:如何在React Hook Form版本7.0上使用onChange

Question

以前我常常这样写：

<input className="form-control" name="productImage" type='file' onChange={handleImageUpload} ref={register({ required: true })} />

在更新之后，我必须这样写：

<input className="form-control" type="file" {...register('productImage', { required: true })} />

如何在更新版本的React Hook窗体上使用onChange={handleImageUpload}？下面是迁移docs

请原谅我在提问方式上的错误。我对这些东西还很陌生。谢谢。

Answer 1

https://github.com/react-hook-form/react-hook-form/releases/tag/v7.16.0

V7.16.0为自定义onChange引入了这个新的API。

<input
  type="text"
  {...register('test', {
    onChange: (e) => {},
    onBlur: (e) => {},
  })}
/>

Answer 2

在register documentation https://react-hook-form.com/api/useform/register中，示例位于Custom onChange, onBlur部分：

// onChange got overwrite by register method
<input onChange={handleChange} {...register('test')} />

// register's onChange got overwrite by register method
<input {...register('test')} onChange={handleChange}/>

const firstName = register('firstName', { required: true })
<input 
  onChange={(e) => {
    firstName.onChange(e); // method from hook form register
    handleChange(e); // your method
  }}
  onBlur={firstName.onBlur}
  ref={firstName.ref} 
/>

因此，对于你的情况：

const productImageRegister = register("productImage", {required: true})
<input className="form-control"
       type="file"
       {...productImageRegister }
       onChange={e => {
           productImageRegister.onChange(e);
           handleImageUpload(e);
       }} />

Answer 3

对我来说，装饰解决方案起作用了。

const fieldRegister = register("productImage", {required: true})
const origOnChange = fieldRegister.onChange
fieldRegister.onChange = (e) => {
    const res = origOnChange(e)
    const value = e.target.value
    // do something with value
    return res
}

对于字段声明，使用

<input {...fieldRegister}/>