未显示 react-hook-form 错误消息

Question

我试图让错误显示在我的页面上，但没有任何反应，我在 console.log() 中得到一个 undefined（如果未填写任何内容）

import React from "react";
import { useForm } from "react-hook-form";

export default function ContactForm() {
  const { register, handleSubmit, watch, formState: { errors } } = useForm();
  const onSubmit = data => console.log(data);

  console.log(watch("example")); // watch input value by passing the name of it

  return (
    <div className="md:w-4/12 ml-auto mr-auto translate-x-1/2 mt-24 w-9/12">
        <form onSubmit={handleSubmit(onSubmit)} className="bg-red-500 p-4">
            {/* register your input into the hook by invoking the "register" function */}
            <label className='text-lg'> email:</label>
                <input label="email" id="email" className="block w-full" {...register("email", {required: true})} />
            {/* include validation with required or other standard HTML validation rules */}
            <label className='text-lg mb-4'>vraag:</label>
                <textarea id="tekst" type="textarea" className="block box-border w-full h-52" {...register("vraag", { required: true })} />

            {/* errors will return when field validation fails  */}
            {errors.exampleRequired && <span className="bg-yellow-400">TEST TEST TEST TEST TEST TEST TEST TEST TEST</span>}
            
            <input type="submit" value="versturen" className="pl-2 mt-2 pr-2 block ml-auto mr-auto cursor-pointer"/>
        </form>
    </div>
  );
}

Answer 1

您需要像这样自己指定错误消息：

{...register("email", { required: "please enter email" })}

然后当出现任何错误时，这就是您显示消息的方式：

{errors.email && (
  <span className="bg-yellow-400">{errors.email.message}</span>
)}

如果您只想一次显示来自所有字段的一条错误消息：

{Object.keys(errors)
  .reverse()
  .reduce(
    (a, field) =>
      errors[field] ? (
        <span className="bg-yellow-400">{errors[field].message}</span>
      ) : (
        a
      ),
    null
  )}

现场演示

参考

https://react-hook-form.com/get-started#Handleerrors

未显示 react-hook-form 错误消息

react-hook-form error message not showing

reactjs

react-hook-form

现场演示

参考