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Form required section in react

there is required section in my form also I want to send successfully text after click of submit button. But problem is here when I click submit button, it shows successfully text no matter form is correct or not. Can you help me about that ? I am beginner :)
My react code here
import React, { Component } from "react";
export default class Form extends Component {
state = {
name: "",
surname: "",
phone: "",
email: "",
comments: "",
// isValid: true,
succesfully: ""
};
/* preventSending = async (e) => {
await this.setState({ [e.target.name]: e.target.value });
if (
this.state.name === "" ||
this.state.surname === "" ||
this.state.phone === "" ||
this.state.email === "" ||
this.state.comments === ""
) {
this.setState({ isValid: true });
} else {
this.setState({ isValid: false });
}
};*/
handleSubmit = (e) => {
this.setState({
succesfully: `${this.state.name} you have sent successfully `
});
};
render() {
return (
<div className="">
<form>
<label htmlFor="name">
Name :
<input
onChange={this.preventSending}
id="name"
name="name"
type="text"
required
/>
</label>
<br />
<label htmlFor="surname">
Surname :
<input
onChange={this.preventSending}
id="surname"
name="surname"
type="text"
required
/>
</label>
<br />
<label htmlFor="phone">
Phone :
<input
onChange={this.preventSending}
id="phone"
name="phone"
type="tel"
required
/>
</label>
<br />
<label htmlFor="email">
Email :
<input
onChange={this.preventSending}
id="email"
name="email"
type="email"
required
/>
</label>
<br />
<label htmlFor="textArea">
Comments :
<textarea
onChange={this.preventSending}
id="textarea"
name="comments"
required
/>
</label>
<br />
<button
type="submit"
// disabled={this.state.isValid}
onClick={this.handleSubmit}
>
Send details{" "}
</button>
</form>
<p>{this.state.succesfully}</p>
</div>
);
}
}
It says I have to add more details but I explained everything clear.

I have to go through your code and try to resolve the errors and get the proper output.
I see that you take the direct state object and update its value, I just corrected that part and also add one error flag in it, so that you can display one informational error message while you click the button without adding the data.
Apart from that, in your form, you take one button which has submit type.
As of now I simply update it with type=button, as type=submit will submit the form and redirect us to new URL.
Please let me know if it is useful to you or not.
here is my code
import React, { Component } from "react";
export default class Form extends Component {
constructor(props) {
super(props);
this.state = {
name: "",
surname: "",
phone: "",
email: "",
comments: "",
// isValid: true,
succesfully: "",
error: "",
};
}
/* preventSending = async (e) => {
await this.setState({ [e.target.name]: e.target.value });
if (
this.state.name === "" ||
this.state.surname === "" ||
this.state.phone === "" ||
this.state.email === "" ||
this.state.comments === ""
) {
this.setState({ isValid: true });
} else {
this.setState({ isValid: false });
}
};*/
handleChange(event) {
const target = event.target;
const value = target.value;
const name = target.name;
this.setState({
[name]: value,
});
}
handleSubmit = (e) => {
if (
this.state.name !== "" &&
this.state.surname !== "" &&
this.state.phone !== "" &&
this.state.email !== "" &&
this.state.comments !== ""
) {
// check valid email or not with regex
const regexp = /^([\w\.\+]{1,})([^\W])(#)([\w]{1,})(\.[\w]{1,})+$/;
let isValidEmail = regexp.test(this.state.email) ? true : false;
if (isValidEmail) {
this.setState({
succesfully: `${this.state.name} you have sent successfully `,
error: "",
});
} else {
this.setState({
succesfully: "",
error: "Please add proper email",
});
}
} else {
this.setState({
succesfully: "",
error: "Please add proper data",
});
}
};
render() {
return (
<div className="">
<form>
<label htmlFor="name">
Name :
<input
onChange={(e) => this.handleChange(e)}
id="name"
name="name"
type="text"
value={this.state.name}
required
/>
</label>
<br />
<label htmlFor="surname">
Surname :
<input
onChange={(e) => this.handleChange(e)}
id="surname"
name="surname"
type="text"
value={this.state.surname}
required
/>
</label>
<br />
<label htmlFor="phone">
Phone :
<input
onChange={(e) => this.handleChange(e)}
id="phone"
name="phone"
type="tel"
value={this.state.phone}
required
/>
</label>
<br />
<label htmlFor="email">
Email :
<input
onChange={(e) => this.handleChange(e)}
id="email"
name="email"
type="email"
value={this.state.email}
required
/>
</label>
<br />
<label htmlFor="textArea">
Comments :
<textarea
onChange={(e) => this.handleChange(e)}
id="textarea"
name="comments"
value={this.state.comments}
required
/>
</label>
<br />
<button
// type="submit" // use this while you want to submit your form
type="button" // I use button to call handleSubmit method and display message
// disabled={this.state.isValid}
onClick={this.handleSubmit}
>
Send details
</button>
</form>
<p>{this.state.succesfully}</p>
<p>{this.state.error}</p>
</div>
);
}
}

I see that the function prevent sending that you created should work except you misplaced the isValid argument:
function ValidateEmail(email)
{
if (/^\w+([\.-]?\w+)*#\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(email))
{
return true
}
return false
}
if (
this.state.name === "" ||
this.state.surname === "" ||
this.state.phone === "" ||
this.state.email === "" ||
this.state.comments === "" ||
!validateEmail(this.state.email)
) {
this.setState({ isValid: false });
} else {
this.setState({ isValid: true });
}
also uncomment disabled and isValid which should be false at the begginning:
// disabled={this.state.isValid}
// isValid = false

React email address format validation

I'm building a portal where students from only 6 universities can participate so I need a way to limit the email address type to these 6 universities for example emails ending with #mit.edu
How do I implement this in React with the form validation set to characters and on clicking on of these formats from the dropdown the email is saved as such for example in the email input field if you write cassandra and select #mit.edu from the dropdown the email becomes cassandra#mit.edu
This is how my login component looks like
`
function LogIn() {
const [password, setPassword] = React.useState("");
const [email, setEmail] = React.useState("");
const [err, setErr] = React.useState(null);
const history = useHistory();
const handleSubmit = async (event, password, email) => {
event.preventDefault();
var myHeaders = new Headers();
myHeaders.set('Authorization', 'Basic ' + encode(email + ":" + password));
var requestOptions = {
method: 'GET',
headers: myHeaders,
redirect: 'follow'
};
let response;
try {
response = await fetch (`${APIlink}/users`, requestOptions)
} catch (err) {
setErr("Incorrect Password. Please Retry.");
return;
}
const result = await response.text();
//console.log(result);
const json = JSON.parse(result);
//console.log(json);
//console.log(response);
if (response.status===200) {
setErr(null);
localStorage.setItem('isAuthenticated', true);
//context.updateToken(JSON.stringify(json.data));
history.push("/Projects");
} else {
setErr(json.error);
console.log(json.error);
}
};
return (
<div>
<Header />
<div className="register row justify-content-center align-items-center">
<div className = "w-50 p-3">
<h1>Log in</h1>
<Link to="/Register">or create a new account</Link>
<br></br>
<br></br>
<form>
<div className="input-group mb-3">
<input type="text" id="email"
value={email}
onChange= {(event) => {
setErr("");
setEmail(event.target.value); }}
className="form-control form-control-lg" placeholder=" institute email" aria-label="institute-email" aria-describedby="basic-addon2"/>
</div>
<small
style={{ color: "red", height: "10px", display: "inline-block" }}
>
{err == "user not found" ? "Account doesn't exist" : ""}
</small>
<div className="input-group mb-3">
<input type="text" id="password"
value={password}
onChange={(event) => {
setPassword(event.target.value);
setErr("");
}}
className="form-control form-control-lg" placeholder="password" aria-label="password" aria-describedby="basic-addon2"/>
</div>
<small
style={{ color: "red", height: "10px", display: "inline-block" }}
>
{err == "incorrect password"
? "Incorrect Password"
: err == "Username and Password can't be empty"
? err
: ""}
</small>
<Submit
//loginState={loginState}
onClick={(event) => {
event.preventDefault();
if (email != "" && password != "") {
handleSubmit(event, password, email);
} else {
setErr("Username and Password can't be empty");
}
}}
>
{" "}
Log In
</Submit>
</form>
</div>
</div>
</div>
)
}
export default LogIn;
`

You can use regex to validate email. Add this validateEmail function right after clicking on submit and pass the email that you want to validate, then proceed further only if it returns true (it will return true if it matches the pattern).
function validateEmail(email)
{
var regex = /^[^\s#]+#mit\.edu$/;
var result = regex.test(email);
if(result == true){
//Proceed further
}
else{
console.log("Enter correct email address!")
}
}
According to this regex, it will return true only if there is exact '#mit.edu' right after any string. Like:-
'anystring#mit.edu' //Returns true
'anystring#mit.com' //Returns false
'anystring#mit.edu.com' //Returns false
You can do this similarly with other domains just replace mit.edu with any other domain or if the domain has more length then simply add '\.domain' for example: -
var regex = /^[^\s#]+#mit\.edu\.com$/;
This will return true if email is 'anystring#mit.edu.com'.
EDIT: A slight correction. Remove '+' after mit and edu, as it returns true on these conditions: -
anystring#mitt.edu
anystring#mit.eduu
Check the regex above now, it should work perfectly.

Formik & Yup: How to validate if the provided date is eighteen years old?

I am working on a form that is made with Formik, Yup, and ReactJS. In the date field, I am trying to validate if the user is 18 years old. I have passed the following as validationSchema paremeter in Formik:
import differenceInYears from "date-fns/differenceInYears";
...
...
...
dob: Yup.date()
.nullable()
.test("dob", "Should be greater than 18", function (value) {
return differenceInYears(value, new Date()) >= 18;
}),
The name of the formik input field is dob. But it shows the validation error even if I enter a valid date which is 18 years old. So, how to validate it properly?

You need to swap the date params:
differenceInYears(new Date(), new Date(value)) >= 18;
If you check date-fns docs, the first argument should be the later date.
Also you need to parse the field value into a Date.

My solution:
import React from "react";
import { Formik, Form, Field } from "formik";
import * as Yup from "yup";
import s from "./Registration.module.css";
const SignupSchema = Yup.object().shape({
firstName: Yup.string().required("Required"),
lastName: Yup.string().required("Required"),
birthdate: Yup.date()
.max(new Date(Date.now() - 567648000000), "You must be at least 18 years")
.required("Required"),
password: Yup.string()
.min(4, "Too Short!")
.max(50, "Too Long!")
.required("Required"),
email: Yup.string().email("Invalid email").required("Required"),
});
export const RegistrationForm = () => (
<div className={s.mainLoginForm}>
<h1>Sign up</h1>
<Formik
initialValues={{
firstName: "",
lastName: "",
email: "",
password: "",
birthdate: "",
}}
validationSchema={SignupSchema}
onSubmit={(values) => {
// same shape as initial values
console.log(values);
}}
>
{({ errors, touched }) => (
<Form>
<div className={s.inputsFlex}>
<Field
className={s.regInput}
placeholder="email"
name="email"
type="email"
/>
{errors.email && touched.email ? (
<div className={s.formControl}>{errors.email}</div>
) : null}
<Field
className={s.regInput}
placeholder="password"
name="password"
type="password"
/>
{errors.password && touched.password ? (
<div className={s.formControl}>{errors.password}</div>
) : null}
<Field
className={s.regInput}
placeholder="firstName"
name="firstName"
/>
{errors.firstName && touched.firstName ? (
<div className={s.formControl}>{errors.firstName}</div>
) : null}
<Field
className={s.regInput}
placeholder="lastName"
name="lastName"
/>
{errors.lastName && touched.lastName ? (
<div className={s.formControl}>{errors.lastName}</div>
) : null}
<Field className={s.regInput} name="birthdate" type="date" />
{errors.birthdate && touched.birthdate ? (
<div className={s.formControl}>{errors.birthdate}</div>
) : null}
<button className={s.regBtn} type="submit">
Sign up
</button>
</div>
</Form>
)}
</Formik>
</div>
);
You can add 4 days for leap (intercalary) year
86 400 000 * 4 = 345 600 000

so if you want to do this without adding the date-fns plugin and dont want to use a mgic number of days then u can do something like this.
dob: Yup.date().nullable()
.test('dob', 'Should be greater than 18', function (value, ctx) {
const dob = new Date(value);
const validDate = new Date();
const valid = validDate.getFullYear() - dob.getFullYear() >= 18;
return !valid ? ctx.createError() : valid;
})
.required('Required'),

Validating variables in the state used in render() to style/populate html

I have the following React Component, which holds a form with two inputs and a button.
export default class Login extends Component {
constructor(props) {
super(props);
this.state = {
email: null,
password: null
}
}
emailInputChanged = (e) => {
this.setState({
email: e.target.value.trim()
});
};
passwordInputChanged = (e) => {
this.setState({
password: e.target.value.trim()
});
};
loginButtonClicked = (e) => {
e.preventDefault();
if (!this.isFormValid()) {
//Perform some API request to validate data
}
};
signupButtonClicked = (e) => {
e.preventDefault();
this.props.history.push('/signup');
};
forgotPasswordButtonClicked = (e) => {
e.preventDefault();
this.props.history.push('/forgot-password');
};
isFormValid = () => {
const {email, password} = this.state;
if (email === null || password === null) {
return false;
}
return isValidEmail(email) && password.length > 0;
};
render() {
const {email, password} = this.state;
return (
<div id="login">
<h1 className="title">Login</h1>
<form action="">
<div className={(!isValidEmail(email) ? 'has-error' : '') + ' input-holder'}>
<Label htmlFor={'loginEmail'} hidden={email !== null && email.length > 0}>email</Label>
<input type="text" className="input" id="loginEmail" value={email !== null ? email : ''}
onChange={this.emailInputChanged}/>
</div>
<div className={(password !== null && password.length === 0 ? 'has-error' : '') + ' input-holder'}>
<Label htmlFor={'loginPassword'}
hidden={password !== null && password.length > 0}>password</Label>
<input type="password" className="input" id="loginPassword"
value={password !== null ? password : ''}
onChange={this.passwordInputChanged}/>
</div>
<button type="submit" className="btn btn-default" id="loginButton"
onClick={this.loginButtonClicked}>
login
</button>
</form>
<div className="utilities">
<a href={'/signup'} onClick={this.signupButtonClicked}>don't have an account?</a>
<a href={'/forgot-password'} onClick={this.forgotPasswordButtonClicked}>forgot your password?</a>
</div>
</div>
)
}
}
export function isValidEmail(email) {
const expression = /\S+#\S+/;
return expression.test(String(email).toLowerCase());
}
The values of the inputs are stored in the component's state. I have given them initial value of null and update them using setState() in the onChange event.
In the render() method I use the state to colour inputs with invalid values. Currently I am only checking the email value against a simple regex and the password to be at least 1 character in length.
The reason I have set the initial values of the state variables to null so I can check in the layout and the initial style on the input to not be marked as "has-errors". However I need to extend the check to:
this.state.email !== null && this.state.email.length === 0
in order to work, because null has no length property.
Is there a cleaner and "React-ish" way to achieve this:
- initial state of the div holding the inputs has no class has-errors
- less checks when setting the value attribute on the input (because React doesn't accept null as value of the attribute)
Edit:
If the initial value of this.state.email and this.state.password are empty strings, I get has-error applied to the div holding the inputs. In my opinion this is bad UX, because the user hasn't done anything and he is already wrong.
The hidden attribute is used by a custom component I made, which acts like "placeholder" (gets erased if something is typed in the input).
Video below showing how my form looks like when this.state.email and this.state.password are empty strings as well how my <Label> component works:

You could create a validate function which return an errors object to know which fields are in error, and use empty strings as initial values. I don't understand what you are trying to do with the hidden attribute.
Edit: add a touched property in the state, to know which field have been touched.
export default class Login extends Component {
constructor(props) {
super(props);
this.state = {
email: '',
password: '',
touched: {},
};
}
emailInputChanged = e => {
this.setState({
email: e.target.value.trim(),
touched: {
...this.state.touched,
email: true,
},
});
};
passwordInputChanged = e => {
this.setState({
password: e.target.value.trim(),
touched: {
...this.state.touched,
password: true,
},
});
};
loginButtonClicked = e => {
e.preventDefault();
if (!this.isFormValid()) {
//Perform some API request to validate data
}
};
isFormValid = () => {
const errors = this.validate();
return Object.keys(errors).length === 0;
};
validate = () => {
const errors = {};
const { email, password } = this.state;
if (!isValidEmail(email)) {
errors.email = true;
}
if (password.length === 0) {
errors.password = true;
}
return errors;
};
render() {
const { email, password, touched } = this.state;
const errors = this.validate();
return (
<div id="login">
<h1 className="title">Login</h1>
<form action="">
<div
className={
(errors.email && touched.email ? 'has-error' : '') +
' input-holder'
}
>
<Label htmlFor={'loginEmail'}>email</Label>
<input
type="text"
className="input"
id="loginEmail"
value={email}
onChange={this.emailInputChanged}
/>
</div>
<div
className={
(errors.password && touched.password ? 'has-error' : '') +
' input-holder'
}
>
<Label htmlFor={'loginPassword'}>password</Label>
<input
type="password"
className="input"
id="loginPassword"
value={password}
onChange={this.passwordInputChanged}
/>
</div>
<button
type="submit"
className="btn btn-default"
id="loginButton"
onClick={this.loginButtonClicked}
>
login
</button>
</form>
</div>
);
}
}
export function isValidEmail(email) {
const expression = /\S+#\S+/;
return expression.test(String(email).toLowerCase());
}

need to accept only numbers in the input field

i am using number type here so that it accepts only number.But i don't want this number type like it's gives increments and decrements selector at the right side of the field.What i need is i need to accept only numbers not any characters.How can i do that?
these are my form elements:
<label className="w3-label w3-text-blue w3-large">
Phone Number:
<input type="number" className="w3-input w3-border" value={this.state.phoneno}
onChange={e => this.setState({ phoneno: e.target.value })} required placeholder="Enter Father's Phone No. in Numbers"/>
</label><br/>
<label className="w3-label w3-text-blue w3-large">
Mobile Number:
<input type="number" className="w3-input w3-border" value={this.state.mobileno} pattern="[0-9]{10}" title="Please enter 10 digit mobile Number"
onChange={e => this.setState({ mobileno: e.target.value })} required placeholder="Enter Father's Mobile No. in Numbers"/>
</label></div><br/>

Try this
input[type=number]::-webkit-inner-spin-button,
input[type=number]::-webkit-outer-spin-button {
-webkit-appearance: none;
margin: 0;
}
https://css-tricks.com/snippets/css/turn-off-number-input-spinners/

You can use regular expressions in javascript to check whether given number is valid or not.
function phonenumber(inputtxt)
{
var phoneno = /^\d{10}$/;
if((inputtxt.value.match(phoneno))
{
return true;
}
else
{
alert("message");
return false;
}
}

This kind of tasks is where React really shines. Just use <input>s with type="text" and let your onChange handlers do the job. I would suggest using String.replace with \D (not a digit) regexp to filter out unwanted chars, and then String.substr to control the length of the entered value. Something like:
const filterNonDigits = value => value ? value.replace(/\D+/, '') : '';
const takeLast = (amount, value) => value ? value.substr(0, amount) : '';
class NumbersInput extends React.Component {
constructor() {
super();
this.state = {};
}
handlePhone(value) {
this.setState({ phoneno: filterNonDigits(value) });
}
handleMobile(value) {
this.setState({ mobileno: takeLast(10, filterNonDigits(value)) });
}
render() {
return (
<div>
<label>
Phone Number:
<input
value={this.state.phoneno}
onChange={e => this.handlePhone(e.target.value)}
/>
</label>
<br/>
<label>
Mobile Number:
<input
value={this.state.mobileno}
onChange={e => this.handleMobile(e.target.value)}
/>
</label>
</div>
);
}
}