如何将 object state 的所有键设置为空数组并在 React js 中仅更改其中一个

Question

I'm creating sign up form with next.js and I'm handling errors with joi.js, After Fetching the data if there is error, I want if the error is in the name input I will pass it as value of the name key in the errors state and pass an empty string to the other keys (email and password), and same thing for other errors, I tried to do it but when there is no error, the keys in the errors state have always the past values.

(Sorry for my bad English)

File where I fetch data Login.tsx

 export default function Login() { const [data, setData] = useState({ name: "", email: "", password: "" }); const [errors, setErrors] = useState({ name: "", email: "", password: "", }); const handleChange = (e) => { setData({...data, [e.target.name]: e.target.value, }); }; const handleSubmit = async (e) => { e.preventDefault(); const res = await fetch("/api/users", { body: JSON.stringify(data), headers: { "Content-Type": "application/json", }, method: "POST", }, { cache: 'no-store' }); const content = await res.json(); if(content.error) { setErrors({...errors, [content.error[0].path[0]]:content.error[0].message}) } console.log(errors); };

 <script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>

Answer 1

There will always be the old values in the errors state variable since you're setting the new error by spreading the old ones first: setErrors({...errors, *****})

What does your content.error contain? I can see you're only accessing the first element ( content.error[0] ), but do you receive all errors for that submission? If you do, you don't need to spread the old errors, just run through all of the reported errors from the response and recreate your errors object.