Question

我想在React的Post中创建编辑Form，所以我的工作流程是获取帖子，表单的setState并显示出来...我试图在功能组件中进行此操作，因为它对我来说易于使用graphql在那里

import React, { useState } from 'react';
import gql from 'graphql-tag';
import { useQuery } from '@apollo/react-hooks';
import useForm from 'react-hook-form';

const GET_POST = gql`
query getPost($id: String!) {
    getPost(id: $id) {
      id
      title
      content
      excerpt
      author {
          name
      }
    }
  }
`;

const EditPost = (props) => {
     //  here Im using postId to fetch post
    const PostID = props.history.location.state.id;
      // Im using react-hook-form
    const { register, errors, reset, handleSubmit } = useForm();
    let POST = { title: '', author: '', content: '', image: '', excerpt: '' };
    //set initial state of form
    const [values, setValues] = useState({
        title: POST.title, author: POST.author, content: POST.content, image: POST.image, excerpt: POST.excerpt
    });


    const { data, loading, error } = useQuery(GET_POST, {
        variables: { id: PostID },
    });

    if (loading) return <p>LOADING</p>;
    if (error) return <p>ERROR</p>;

    const fetchedPost = data.getPost;
    // here is a problem I would like when post is fetched to set those values to state & then use it to make form reactive ???
   if (fetchedPost) {
        const { title, author, content, image, excerpt } = fetchedPost;

    }

    return (
        <div className="edit-form">
            <h2>Edit Post</h2>
            <fieldset>
                <form>
                    <p className="form-group">
                        <label htmlFor="title">Post Title: </label>
                        <input type="text" name="title" id="name"
                            value={values.title}
                            aria-invalid={errors.title ? 'true' : 'false'}
                            aria-describedby="error-title-required error-title-maxLength"
                            ref={register({ required: true, maxlength: 20 })}
                            placeholder="Name" />
                        <span>{errors.title && 'Title is required'} </span>
                    </p>

                </form>
            </fieldset>

        </div>);
}


export default EditPost;

问题是当我获取帖子时，我不知道如何设置表单的状态以及如何使表单具有反应性？

Answer 1

请参阅文档：https://github.com/react-hook-form/react-hook-form/blob/fa5e71ca5eef76ae29b9cda774061051e5182162/examples/customValidation.tsx


  const intialValues = {
    firstName: 'bill',
    lastName: 'luo',
    email: 'bluebill1049@hotmail.com',
    age: -1,
  };

      <input
        defaultValue={intialValues.firstName}
        name="firstName"
        placeholder="bill"
        ref={register({
          validate: value => value !== 'bill',
        })}
      />

用值预填充React Form

1 个答案: