input filld not getting while typing - reactjs

in input tag while i placed value attribute in it it not getting input from keybord not showing input
import React from 'react'
class Postform extends React.Component {
state = {
name: 'helo',
email: '',
password: '',
bio: '',
};
changeHandler = (event) => {};
submitHandler = (event) => {
event.preventDefault();
};
render() {
return (
<div className="container">
<form onSubmit={this.submitHandler}>
<div classNam=" form-group ">
<label htmlFor="name">Enter your name </label>
<input
placeholder="Enter your name"
id="name"
className="form-control"
name="name"
onChange={this.changeHandler}
value="hello"
/>
</div>
<button type="submit" className="btn btn-info">
submit
</button>
</form>
</div>
);
}
}
export default Postform;

You set the input value to be hello this means that it will stay hello no matter what.
To make the input value dynamic you going to need to set the value from the state of your component as the input value.
This means that you also going to have to update the state when the input value changes using the changeHandler.
Lets start from the input
// Always read the input value from state
// and when the input value changes call this.changeHandler
<input onChange={this.changeHandler} value={this.state.name} />
Then the changeHandler
changeHandler = (event) => {
// The input value has been changed, get the value from
// event.target.value and set it as state.
this.setState({ name: event.target.value });
};
Now the state will be updated and the component will re-render the input with the current state.name as the value

Related

remove the value enterd in input fild after submistion :react js [duplicate]

I have a form containing various input fields and two buttons; one for submitting and one for cancelling.
<form id="create-course-form">
<input type="text" name="course_Name" ref="fieldName">
<input type="text" name="course_org" ref="fieldOrg">
<input type="text" name="course_Number" ref="fieldNum">
<input type="submit" name="saveCourse" value="Create">
<input type="button" name="cancelCourse" value="cancel" onClick={this.cancelCourse}>
</form>
What I want is to empty all inputs when the cancel button is clicked. So far I've managed to do this by using each input's ref prop.
cancelCourse(){
this.refs.fieldName.value="";
this.refs.fieldorg.value="";
this.refs.fieldNum.value="";
}
However, I want to empty the input fields without having to empty each one seperately. I want something similar to this (jQuery): $('#create-course-form input[type=text]').val('');
The answer here depends on whether or not your inputs are controlled or uncontrolled. If you are unsure or need more info on this, check out what the official docs say about controlled components and uncontrolled components. Thanks #Dan-Esparza for providing the links.
Also, please note that using string literals in ref is deprecated. Use the standard callback method instead.
Clearing a form with uncontrolled fields
You can clear the entire form rather than each form field individually.
cancelCourse = () => {
document.getElementById("create-course-form").reset();
}
render() {
return (
<form id="create-course-form">
<input />
<input />
...
<input />
</form>
);
}
If your form didn't have an id attribute you could use a ref as well:
cancelCourse = () => {
this.myFormRef.reset();
}
render() {
return (
<form ref={(el) => this.myFormRef = el;}>
<input />
<input />
...
<input />
</form>
);
}
Clearing a form with controlled fields
If you are using controlled form fields, you may have to explicitly reset each component inside your form, depending on how your values are stored in the state.
If they are declared individually, you need to reset each one explicitly:
cancelCourse = () => {
this.setState({
inputVal_1: "",
inputVal_2: "",
...
inputVal_n: "",
});
}
render() {
return (
<input value={this.state.inputVal_1} onChange={this.handleInput1Change}>
<input value={this.state.inputVal_2} onChange={this.handleInput2Change}>
...
<input value={this.state.inputVal_n} onChange={this.handleInputnChange}>
);
}
Demo below:
class MyApp extends React.Component {
constructor() {
super();
this.state = {
inputVal_1: "",
inputVal_2: "",
inputVal_3: "",
inputVal_4: "",
inputVal_5: "",
inputVal_6: "",
inputVal_7: "",
inputVal_8: "",
inputVal_9: "",
inputVal_10: ""
};
}
handleInput1Change = (e) => {
this.setState({inputVal_1: e.target.value});
}
handleInput2Change = (e) => {
this.setState({inputVal_2: e.target.value});
}
handleInput3Change = (e) => {
this.setState({inputVal_3: e.target.value});
}
handleInput4Change = (e) => {
this.setState({inputVal_4: e.target.value});
}
handleInput5Change = (e) => {
this.setState({inputVal_5: e.target.value});
}
handleInput6Change = (e) => {
this.setState({inputVal_6: e.target.value});
}
handleInput7Change = (e) => {
this.setState({inputVal_7: e.target.value});
}
handleInput8Change = (e) => {
this.setState({inputVal_8: e.target.value});
}
handleInput9Change = (e) => {
this.setState({inputVal_9: e.target.value});
}
handleInput10Change = (e) => {
this.setState({inputVal_10: e.target.value});
}
cancelCourse = () => {
this.setState({
inputVal_1: "",
inputVal_2: "",
inputVal_3: "",
inputVal_4: "",
inputVal_5: "",
inputVal_6: "",
inputVal_7: "",
inputVal_8: "",
inputVal_9: "",
inputVal_10: ""
});
}
render() {
return (
<form>
<input value={this.state.inputVal_1} onChange={this.handleInput1Change} />
<input value={this.state.inputVal_2} onChange={this.handleInput2Change} />
<input value={this.state.inputVal_3} onChange={this.handleInput3Change} />
<input value={this.state.inputVal_4} onChange={this.handleInput4Change} />
<input value={this.state.inputVal_5} onChange={this.handleInput5Change} />
<input value={this.state.inputVal_6} onChange={this.handleInput6Change} />
<input value={this.state.inputVal_7} onChange={this.handleInput7Change} />
<input value={this.state.inputVal_8} onChange={this.handleInput8Change} />
<input value={this.state.inputVal_9} onChange={this.handleInput9Change} />
<input value={this.state.inputVal_10} onChange={this.handleInput10Change} />
<input type="submit" name="saveCourse" value="Create" />
<input type="button" name="cancelCourse" value="cancel" onClick={this.cancelCourse} />
</form>
);
}
}
ReactDOM.render(<MyApp />, document.getElementById("app"));
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="app"></div>
There is a cleaner way to do this though. Rather than having n state properties and n event handlers, one for each input, with some clever coding we can reduce the code dramatically.
In the constructor we just declare an empty object, which will be used to hold input values. We use only one input handler and pass it the index of the input element we want to change the value of. This means that the value of an individual input is generated the moment we start typing into it.
To reset the form, we only need to set our input object back to being empty again.
The input value is this.state.inputVal[i]. If i doesn't exist (we haven't typed anything yet into that input) we want the value to be an empty string (instead of null).
cancelCourse = () => {
this.setState({inputVal: {}});
}
render() {
return (
<form>
{[...Array(n)].map(
(item, i) => <input value={this.state.inputVal[i] || ""} onChange={this.handleInputChange.bind(this, i)} />
)}
</form>
);
}
Demo below:
class MyApp extends React.Component {
constructor() {
super();
this.state = {
inputVal: {}
};
}
handleInputChange = (idx, {target}) => {
this.setState(({inputVal}) => {
inputVal[idx] = target.value;
return inputVal;
});
}
cancelCourse = () => {
this.setState({inputVal: {}});
}
render() {
return(
<form>
{[...Array(10)].map( //create an array with a length of 10
(item, i) => <input value={this.state.inputVal[i] || ""} onChange={this.handleInputChange.bind(this, i)} /> //bind the index to the input handler
)}
<input type="submit" name="saveCourse" value="Create" />
<input type="button" name="cancelCourse" value="cancel" onClick={this.cancelCourse} />
</form>
);
}
}
ReactDOM.render(<MyApp />, document.getElementById("app"));
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="app"></div>
Very easy:
handleSubmit(e){
e.preventDefault();
e.target.reset();
}
// If using class component
<form onSubmit={this.handleSubmit.bind(this)}>
...
</form>
// If using function component
<form onSubmit={handleSubmit}>
...
</form>
Using event.target.reset() only works for uncontrolled components, which is not recommended. For controlled components you would do something like this:
import React, { Component } from 'react'
class MyForm extends Component {
initialState = { name: '' }
state = this.initialState
handleFormReset = () => {
this.setState(() => this.initialState)
}
render() {
return (
<form onReset={this.handleFormReset}>
<div>
<label htmlFor="name">Name</label>
<input
type="text"
placeholder="Enter name"
name="name"
value={name}
onChange={this.handleInputOnChange}
/>
</div>
<div>
<input
type="submit"
value="Submit"
/>
<input
type="reset"
value="Reset"
/>
</div>
</form>
)
}
}
ContactAdd.propTypes = {}
export default MyForm
You can also do it by targeting the current input, with anything.target.reset() . This is the most easiest way!
handleSubmit(e){
e.preventDefault();
e.target.reset();
}
<form onSubmit={this.handleSubmit}>
...
</form>
Here's an update to Chris's answer above, using modern React hooks.
Same high level idea; your form can be either a Controlled or Uncontrolled component.
Uncontrolled components:
Uncontrolled components leave state management up to the browser. That means you have to ask the browser to reset the form inputs. To do that, capture the form element as a ref, and then call the submit() method on that element.
export default function Form() {
const ref = React.useRef();
function reset(ev) {
ev.preventDefault();
ref.current.reset();
}
return (
<form ref={ref}>
<label htmlFor="email">Email Address</label>
<input id="email" type="email" name="email" />
<label htmlFor="message">Message</label>
<textarea id="message" name="message" />
<button type="submit">Submit</button>
<button onClick={reset}>Reset</button>
</form>
);
}
Controlled components:
With a controlled component, you manage the state in React. That means you have to create the initial state, and update it every time an input changes. In this world, resetting the form is just a matter of setting the form state back to its initial state.
export default function Form() {
const [state, setState] = React.useState({ email: "", message: "" });
function reset(ev) {
ev.preventDefault();
setState({ email: "", message: "" });
}
return (
<form className="Form">
<label htmlFor="email">Email Address</label>
<input
id="email"
type="email"
name="email"
value={state.email}
onChange={(ev) => {
setState({ ...state, email: ev.target.value });
}}
/>
<label htmlFor="message">Message</label>
<textarea
id="message"
name="message"
value={state.message}
onChange={(ev) => {
setState({ ...state, message: ev.target.value });
}}
/>
<button type="submit">Submit</button>
<button onClick={reset}>Reset</button>
</form>
);
}
Full example at https://codesandbox.io/s/reactformreset-10cjn3
Following code should reset the form in one click.
import React, { Component } from 'react';
class App extends Component {
constructor(props){
super(props);
this.handleSubmit=this.handleSubmit.bind(this);
}
handleSubmit(e){
this.refs.form.reset();
}
render(){
return(
<div>
<form onSubmit={this.handleSubmit} ref="form">
<input type="text" placeholder="First Name!" ref='firstName'/><br/<br/>
<input type="text" placeholder="Last Name!" ref='lastName'/><br/><br/>
<button type="submit" >submit</button>
</form>
</div>
}
}
To clear your form, admitted that your form's elements values are saved in your state, you can map through your state like that :
// clear all your form
Object.keys(this.state).map((key, index) => {
this.setState({[key] : ""});
});
If your form is among other fields, you can simply insert them in a particular field of the state like that:
state={
form: {
name:"",
email:""}
}
// handle set in nested objects
handleChange = (e) =>{
e.preventDefault();
const newState = Object.assign({}, this.state);
newState.form[e.target.name] = e.target.value;
this.setState(newState);
}
// submit and clear state in nested object
onSubmit = (e) =>{
e.preventDefault();
var form = Object.assign({}, this.state.form);
Object.keys(form).map((key, index) => {
form[key] = "" ;
});
this.setState({form})
}
This one works best to reset the form.
import React, { Component } from 'react'
class MyComponent extends Component {
constructor(props){
super(props)
this.state = {
inputVal: props.inputValue
}
// preserve the initial state in a new object
this.baseState = this.state ///>>>>>>>>> note this one.
}
resetForm = () => {
this.setState(this.baseState) ///>>>>>>>>> note this one.
}
submitForm = () => {
// submit the form logic
}
updateInput = val => this.setState({ inputVal: val })
render() {
return (
<form>
<input
onChange={this.updateInput}
type="text
value={this.state.inputVal} />
<button
onClick={this.resetForm}
type="button">Cancel</button>
<button
onClick={this.submitForm}
type="submit">Submit</button>
</form>
)
}
}
When the form is submitted, the 'event' will be passed as an argument to the handleSubmit method, and if that you can access the <form> element by typing event.target. then you just need to reset the form using .reset() form method.
https://developer.mozilla.org/en-US/docs/Web/API/HTMLFormElement/reset
handleSubmit = (event)=>{
event.preventDefault()
....
event.target.reset()
}
render() {
return (
<>
<form onSubmit={this.handleSubmit}>
<label htmlFor='movieTitle'>Title</label>
<input name='movieTitle' id='movieTitle' type='text' />
<input type='submit' value='Find Movie Info' />
</form>
</>
)
}
I don't know if this is still relevant. But when I had similar issue this is how I resolved it.
Where you need to clear an uncontrolled form you simply do this after submission.
this.<ref-name-goes-here>.setState({value: ''});
Hope this helps.
import React, { Component } from 'react'
export default class Form extends Component {
constructor(props) {
super(props)
this.formRef = React.createRef()
this.state = {
email: '',
loading: false,
eror: null
}
}
reset = () => {
this.formRef.current.reset()
}
render() {
return (
<div>
<form>
<input type="email" name="" id=""/>
<button type="submit">Submit</button>
<button onClick={()=>this.reset()}>Reset</button>
</form>
</div>
)
}
}
/*
See newState and use of it in eventSubmit() for resetting all the state.
I have tested it is working for me. Please let me know for mistakes
*/
import React from 'react';
const newState = {
fullname: '',
email: ''
}
class Form extends React.Component {
constructor(props) {
super(props);
this.state = {
fullname: ' ',
email: ' '
}
this.eventChange = this
.eventChange
.bind(this);
this.eventSubmit = this
.eventSubmit
.bind(this);
}
eventChange(event) {
const target = event.target;
const value = target.type === 'checkbox'
? target.type
: target.value;
const name = target.name;
this.setState({[name]: value})
}
eventSubmit(event) {
alert(JSON.stringify(this.state))
event.preventDefault();
this.setState({...newState});
}
render() {
return (
<div className="container">
<form className="row mt-5" onSubmit={this.eventSubmit}>
<label className="col-md-12">
Full Name
<input
type="text"
name="fullname"
id="fullname"
value={this.state.fullname}
onChange={this.eventChange}/>
</label>
<label className="col-md-12">
email
<input
type="text"
name="email"
id="email"
value={this.state.value}
onChange={this.eventChange}/>
</label>
<input type="submit" value="Submit"/>
</form>
</div>
)
}
}
export default Form;
the easiest way is doing it regularly with just HTML and using the button type "reset" there is no need to mess with anything in react at all, no state, no nothing.
import React, {useState} from 'react'
function HowReactWorks() {
return (
<div>
<form>
<div>
<label for="name">Name</label>
<input type="text" id="name" placeholder="name" />
</div>
<div>
<label for="password">Password</label>
<input type="password" id="password" placeholder="password" />
</div>
<button type="reset">Reset</button>
<button>Submit</button>
</form>
</div>
)
}
export default HowReactWorks
edited for the people that don't know how to include HTML in react
You can use this method as well
const resetData = (e) => {
e.preventDefault();
settitle("");
setdate("");
};
<input type="text" onChange={(e) => settitle(e.target.value)} value={title} />
<input type="date" onChange={(e) => setdate(e.target.value)} value={date} />
<button onClick={resetData}>Reset Data</button>
This is the solution that worked for me, in the case of parent component triggering reset of child controlled input components:
const ParentComponent = () => {
const [reset, setReset] = useState()
const submitHandler = (e) => {
e.preventDefault()
//do your stuff
setReset(Date.now()) // pass some value to trigger update
}
return (
<form onSubmit={submitHandler}>
<ChildInputComponent reset={reset} />
<ChildInputComponent reset={reset} />
</form>
)
}
const ChildInputComponent = ({reset}) => {
const [value, setValue] = useState()
useEffect(() => {
setValue('')
}, [reset])
return <input value={value} onChange={(e) => setValue(e.target.value)} />
}
Assuming you declared
const [inputs, setInputs] = useState([]);
As multiple parameters. You can actually reset the items using this syntax:
setInputs([]);
Just in case, this how you define handleChange.
You can use this form or any ways you want.
const handleChange = (event) => {
const name = event.target.name;
const email = event.target.email;
const message = event.target.message;
const value = event.target.value;
setInputs(values => ({...values, [name]: value, [email]: value, [message]: value}))
}
You can use this form as an example.
<form onSubmit={handleSubmit}>
<div className="fields">
<div className="field half">
<label for="name">Name</label>
<input value={inputs.name || ''} type="text" name="name" id="nameId" onChange={handleChange} maxLength="30" />
</div>
<div className="field half">
<label for="email">Email</label>
<input value={inputs.email || ''} type="text" name="email" id="emailId" onChange={handleChange} maxLength="40"/>
</div>
<div className="field">
<label for="message">Message</label>
<textarea value={inputs.message || ''} name="message" id="messageId" rows="6" onChange={handleChange} maxLength="400" />
</div>
</div>
<ul className="actions">
<li><input type="submit" value="Send Message" className="primary" /></li>
<li><input onClick={resetDetails} type="reset" value="Clear" /></li>
</ul>
</form>
This is just one of many ways to declare forms. Good luck!
const onReset = () => {
form.resetFields();
};
state={
name:"",
email:""
}
handalSubmit = () => {
after api call
let resetFrom = {}
fetch('url')
.then(function(response) {
if(response.success){
resetFrom{
name:"",
email:""
}
}
})
this.setState({...resetFrom})
}
Why not use HTML-controlled items such as <input type="reset">

how to perform crud operation in react with firebase database

I am trying on trial and error basis. I tried to insert username and password in the database using reactjs by event handling, but whenever I enter the username and the password both fields get the same value. For example, if I put 'ABC' as username and 123 as password then the username and password will get same value 123 in the database.
1.trying to insert data using event handling.
class Login extends Component{
ref = firebase.firestore().collection('login');
state = {
username: '',
password: ''
};
handleChange = (event) => {
const state = this.state
state.username = event.target.value;
state.password=event.target.value;
//console.log(state[event.target.username]);
//console.log(state[event.target.password]);
this.setState({username:state.username,
password:state.password });
console.log(state.username);
console.log(state.password);
}
onSubmit = (event) => {
event.preventDefault();
const { username,password } = this.state;
this.ref.add({
username,
password
}).then((docRef) => {
this.setState({
username: '',
password:''
});
this.props.history.push("/")
})
.catch((error) => {
console.error("Error adding document: ", error);
});
}
render()
{
return(
<form onSubmit={this.onSubmit}>
<div className="container mt-5 w-50">
<div className="form-group">
<label for= "user name" className="">User Name:</label>
<input type="text" name="userName" placeholder="UserName" className="form-control w-50" onChange={this.handleChange.bind(this)}/><br/>
<label for="password" className="">Password:</label>
<input type="password" name="password" placeholder="password" className="form-control w-50" onChange={this.handleChange.bind(this)}/><br/>
<button name="Login" className="btn btn-success w-50 mb-3">Login</button><br/>
{/* Don't Have an Account? SignUp */}
<Link to="/signup">Don't Have an Account? SignUp</Link>
</div>
</div>
</form>
);
}
}
export default Login;
username and password should get their actual values.
I believe this is because you are setting the state of both to the same value (event.target.value) in your event handler. You're also mutating state which is not a good thing to do in any situation.
in your handleChange function you are changing username AND password state values to the value of event.target.value which will happen when onChange fires in whichever input you are using handleChange as a listener.
change your handleChange function to this:
handleChange = event => {
let {name, value} = event.target;
this.setState({
[name]: value
});
}
by using {[name]: value} when the event fires in an input with name="password" the password value in your component's state will update
Your render function is a bit confusing but I am going to assume you're rendering a form with labels for username and password...
then in your input within your form (which I can't see in your markdown above, but I'm assuming is in the Login component):
<input name="username" value={this.state.username} onChange={this.handleChange} />
<input name="password" value={this.state.password} onChange={this.handleChange} />

Setting the default value of an input field after data is retrieved causes the content to overlap and the "onChange" event not to be triggered

I have an "edit category" component in my React application.
The ID is passed through the URL.
When the component is mounted, the action "fetchCategory" is called, which updates the props on the component with the current category.
I have a form which I want to be pre-populated, which I'm currently doing using the defaultValue on the input.
However, this isn't reflected on the state and the label for the text field overlaps the input field.
Any help would be greatly appreciated. I'll leave snippets of my code below which could help with understanding what I'm trying to do.
import React, { Component } from "react";
import { connect } from "react-redux";
import { fetchCategory } from "../../store/actions/categoryActions";
class AddOrEditCategory extends Component {
componentDidMount() {
this.props.fetchCategory(this.props.match.params.id);
if (this.props.match.params.id) {
this.setState({
_id: this.props.match.params.id
});
}
}
handleSubmit = e => {
e.preventDefault();
console.log(this.state);
};
handleChange = e => {
this.setState({
[e.target.id]: e.target.value
});
};
render() {
const addingNew = this.props.match.params.id === undefined;
return (
<div className="container">
<h4>{addingNew ? "Add category" : "Edit category"}</h4>
<form onSubmit={this.handleSubmit}>
<div className="input-field">
<input
type="text"
id="name"
defaultValue={this.props.category.name}
onChange={this.handleChange}
/>
<label htmlFor="name">Category name</label>
</div>
<div className="input-field">
<input
type="text"
id="urlKey"
onChange={this.handleChange}
defaultValue={this.props.category.urlKey}
/>
<label htmlFor="urlKey">URL Key</label>
</div>
<button className="btn">{addingNew ? "Add" : "Save"}</button>
</form>
</div>
);
}
}
const mapStateToProps = state => {
return {
category: state.categoryReducer.category
};
};
export default connect(
mapStateToProps,
{ fetchCategory }
)(AddOrEditCategory);
EDIT: Included whole component as requested
You need to replace the 'defaultValue' attribute with 'value' in the inputs.
You are using a controlled vs uncontrolled component. You dont need to use defaultValue.
You can set the initial values on the promise success for fetchCategory
componentDidMount() {
this.props.fetchCategory(this.props.match.params.id).then(response => {
// Set the initial state here
}
}
OR in
componentWillReceiveProps(nextProps) {
// Compare current props with next props to see if there is a change
// in category data received from action fetchCategory and set the initial state
}
React docs
<form onSubmit={this.handleSubmit}>
<div className="input-field">
<input
type="text"
id="name"
onChange={this.handleChange}
value={this.state.name} //<---
/>
<label htmlFor="name">Category name</label>
</div>
<div className="input-field">
<input
type="text"
id="urlKey"
onChange={this.handleChange}
value={this.state.urlKey}
/>
<label htmlFor="urlKey">URL Key</label>
</div>
<button className="btn">{addingNew ? "Add" : "Save"}</button>
</form>

Clear and reset form input fields

I have a form containing various input fields and two buttons; one for submitting and one for cancelling.
<form id="create-course-form">
<input type="text" name="course_Name" ref="fieldName">
<input type="text" name="course_org" ref="fieldOrg">
<input type="text" name="course_Number" ref="fieldNum">
<input type="submit" name="saveCourse" value="Create">
<input type="button" name="cancelCourse" value="cancel" onClick={this.cancelCourse}>
</form>
What I want is to empty all inputs when the cancel button is clicked. So far I've managed to do this by using each input's ref prop.
cancelCourse(){
this.refs.fieldName.value="";
this.refs.fieldorg.value="";
this.refs.fieldNum.value="";
}
However, I want to empty the input fields without having to empty each one seperately. I want something similar to this (jQuery): $('#create-course-form input[type=text]').val('');
The answer here depends on whether or not your inputs are controlled or uncontrolled. If you are unsure or need more info on this, check out what the official docs say about controlled components and uncontrolled components. Thanks #Dan-Esparza for providing the links.
Also, please note that using string literals in ref is deprecated. Use the standard callback method instead.
Clearing a form with uncontrolled fields
You can clear the entire form rather than each form field individually.
cancelCourse = () => {
document.getElementById("create-course-form").reset();
}
render() {
return (
<form id="create-course-form">
<input />
<input />
...
<input />
</form>
);
}
If your form didn't have an id attribute you could use a ref as well:
cancelCourse = () => {
this.myFormRef.reset();
}
render() {
return (
<form ref={(el) => this.myFormRef = el;}>
<input />
<input />
...
<input />
</form>
);
}
Clearing a form with controlled fields
If you are using controlled form fields, you may have to explicitly reset each component inside your form, depending on how your values are stored in the state.
If they are declared individually, you need to reset each one explicitly:
cancelCourse = () => {
this.setState({
inputVal_1: "",
inputVal_2: "",
...
inputVal_n: "",
});
}
render() {
return (
<input value={this.state.inputVal_1} onChange={this.handleInput1Change}>
<input value={this.state.inputVal_2} onChange={this.handleInput2Change}>
...
<input value={this.state.inputVal_n} onChange={this.handleInputnChange}>
);
}
Demo below:
class MyApp extends React.Component {
constructor() {
super();
this.state = {
inputVal_1: "",
inputVal_2: "",
inputVal_3: "",
inputVal_4: "",
inputVal_5: "",
inputVal_6: "",
inputVal_7: "",
inputVal_8: "",
inputVal_9: "",
inputVal_10: ""
};
}
handleInput1Change = (e) => {
this.setState({inputVal_1: e.target.value});
}
handleInput2Change = (e) => {
this.setState({inputVal_2: e.target.value});
}
handleInput3Change = (e) => {
this.setState({inputVal_3: e.target.value});
}
handleInput4Change = (e) => {
this.setState({inputVal_4: e.target.value});
}
handleInput5Change = (e) => {
this.setState({inputVal_5: e.target.value});
}
handleInput6Change = (e) => {
this.setState({inputVal_6: e.target.value});
}
handleInput7Change = (e) => {
this.setState({inputVal_7: e.target.value});
}
handleInput8Change = (e) => {
this.setState({inputVal_8: e.target.value});
}
handleInput9Change = (e) => {
this.setState({inputVal_9: e.target.value});
}
handleInput10Change = (e) => {
this.setState({inputVal_10: e.target.value});
}
cancelCourse = () => {
this.setState({
inputVal_1: "",
inputVal_2: "",
inputVal_3: "",
inputVal_4: "",
inputVal_5: "",
inputVal_6: "",
inputVal_7: "",
inputVal_8: "",
inputVal_9: "",
inputVal_10: ""
});
}
render() {
return (
<form>
<input value={this.state.inputVal_1} onChange={this.handleInput1Change} />
<input value={this.state.inputVal_2} onChange={this.handleInput2Change} />
<input value={this.state.inputVal_3} onChange={this.handleInput3Change} />
<input value={this.state.inputVal_4} onChange={this.handleInput4Change} />
<input value={this.state.inputVal_5} onChange={this.handleInput5Change} />
<input value={this.state.inputVal_6} onChange={this.handleInput6Change} />
<input value={this.state.inputVal_7} onChange={this.handleInput7Change} />
<input value={this.state.inputVal_8} onChange={this.handleInput8Change} />
<input value={this.state.inputVal_9} onChange={this.handleInput9Change} />
<input value={this.state.inputVal_10} onChange={this.handleInput10Change} />
<input type="submit" name="saveCourse" value="Create" />
<input type="button" name="cancelCourse" value="cancel" onClick={this.cancelCourse} />
</form>
);
}
}
ReactDOM.render(<MyApp />, document.getElementById("app"));
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="app"></div>
There is a cleaner way to do this though. Rather than having n state properties and n event handlers, one for each input, with some clever coding we can reduce the code dramatically.
In the constructor we just declare an empty object, which will be used to hold input values. We use only one input handler and pass it the index of the input element we want to change the value of. This means that the value of an individual input is generated the moment we start typing into it.
To reset the form, we only need to set our input object back to being empty again.
The input value is this.state.inputVal[i]. If i doesn't exist (we haven't typed anything yet into that input) we want the value to be an empty string (instead of null).
cancelCourse = () => {
this.setState({inputVal: {}});
}
render() {
return (
<form>
{[...Array(n)].map(
(item, i) => <input value={this.state.inputVal[i] || ""} onChange={this.handleInputChange.bind(this, i)} />
)}
</form>
);
}
Demo below:
class MyApp extends React.Component {
constructor() {
super();
this.state = {
inputVal: {}
};
}
handleInputChange = (idx, {target}) => {
this.setState(({inputVal}) => {
inputVal[idx] = target.value;
return inputVal;
});
}
cancelCourse = () => {
this.setState({inputVal: {}});
}
render() {
return(
<form>
{[...Array(10)].map( //create an array with a length of 10
(item, i) => <input value={this.state.inputVal[i] || ""} onChange={this.handleInputChange.bind(this, i)} /> //bind the index to the input handler
)}
<input type="submit" name="saveCourse" value="Create" />
<input type="button" name="cancelCourse" value="cancel" onClick={this.cancelCourse} />
</form>
);
}
}
ReactDOM.render(<MyApp />, document.getElementById("app"));
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="app"></div>
Very easy:
handleSubmit(e){
e.preventDefault();
e.target.reset();
}
// If using class component
<form onSubmit={this.handleSubmit.bind(this)}>
...
</form>
// If using function component
<form onSubmit={handleSubmit}>
...
</form>
Using event.target.reset() only works for uncontrolled components, which is not recommended. For controlled components you would do something like this:
import React, { Component } from 'react'
class MyForm extends Component {
initialState = { name: '' }
state = this.initialState
handleFormReset = () => {
this.setState(() => this.initialState)
}
render() {
return (
<form onReset={this.handleFormReset}>
<div>
<label htmlFor="name">Name</label>
<input
type="text"
placeholder="Enter name"
name="name"
value={name}
onChange={this.handleInputOnChange}
/>
</div>
<div>
<input
type="submit"
value="Submit"
/>
<input
type="reset"
value="Reset"
/>
</div>
</form>
)
}
}
ContactAdd.propTypes = {}
export default MyForm
You can also do it by targeting the current input, with anything.target.reset() . This is the most easiest way!
handleSubmit(e){
e.preventDefault();
e.target.reset();
}
<form onSubmit={this.handleSubmit}>
...
</form>
Here's an update to Chris's answer above, using modern React hooks.
Same high level idea; your form can be either a Controlled or Uncontrolled component.
Uncontrolled components:
Uncontrolled components leave state management up to the browser. That means you have to ask the browser to reset the form inputs. To do that, capture the form element as a ref, and then call the submit() method on that element.
export default function Form() {
const ref = React.useRef();
function reset(ev) {
ev.preventDefault();
ref.current.reset();
}
return (
<form ref={ref}>
<label htmlFor="email">Email Address</label>
<input id="email" type="email" name="email" />
<label htmlFor="message">Message</label>
<textarea id="message" name="message" />
<button type="submit">Submit</button>
<button onClick={reset}>Reset</button>
</form>
);
}
Controlled components:
With a controlled component, you manage the state in React. That means you have to create the initial state, and update it every time an input changes. In this world, resetting the form is just a matter of setting the form state back to its initial state.
export default function Form() {
const [state, setState] = React.useState({ email: "", message: "" });
function reset(ev) {
ev.preventDefault();
setState({ email: "", message: "" });
}
return (
<form className="Form">
<label htmlFor="email">Email Address</label>
<input
id="email"
type="email"
name="email"
value={state.email}
onChange={(ev) => {
setState({ ...state, email: ev.target.value });
}}
/>
<label htmlFor="message">Message</label>
<textarea
id="message"
name="message"
value={state.message}
onChange={(ev) => {
setState({ ...state, message: ev.target.value });
}}
/>
<button type="submit">Submit</button>
<button onClick={reset}>Reset</button>
</form>
);
}
Full example at https://codesandbox.io/s/reactformreset-10cjn3
Following code should reset the form in one click.
import React, { Component } from 'react';
class App extends Component {
constructor(props){
super(props);
this.handleSubmit=this.handleSubmit.bind(this);
}
handleSubmit(e){
this.refs.form.reset();
}
render(){
return(
<div>
<form onSubmit={this.handleSubmit} ref="form">
<input type="text" placeholder="First Name!" ref='firstName'/><br/<br/>
<input type="text" placeholder="Last Name!" ref='lastName'/><br/><br/>
<button type="submit" >submit</button>
</form>
</div>
}
}
To clear your form, admitted that your form's elements values are saved in your state, you can map through your state like that :
// clear all your form
Object.keys(this.state).map((key, index) => {
this.setState({[key] : ""});
});
If your form is among other fields, you can simply insert them in a particular field of the state like that:
state={
form: {
name:"",
email:""}
}
// handle set in nested objects
handleChange = (e) =>{
e.preventDefault();
const newState = Object.assign({}, this.state);
newState.form[e.target.name] = e.target.value;
this.setState(newState);
}
// submit and clear state in nested object
onSubmit = (e) =>{
e.preventDefault();
var form = Object.assign({}, this.state.form);
Object.keys(form).map((key, index) => {
form[key] = "" ;
});
this.setState({form})
}
This one works best to reset the form.
import React, { Component } from 'react'
class MyComponent extends Component {
constructor(props){
super(props)
this.state = {
inputVal: props.inputValue
}
// preserve the initial state in a new object
this.baseState = this.state ///>>>>>>>>> note this one.
}
resetForm = () => {
this.setState(this.baseState) ///>>>>>>>>> note this one.
}
submitForm = () => {
// submit the form logic
}
updateInput = val => this.setState({ inputVal: val })
render() {
return (
<form>
<input
onChange={this.updateInput}
type="text
value={this.state.inputVal} />
<button
onClick={this.resetForm}
type="button">Cancel</button>
<button
onClick={this.submitForm}
type="submit">Submit</button>
</form>
)
}
}
When the form is submitted, the 'event' will be passed as an argument to the handleSubmit method, and if that you can access the <form> element by typing event.target. then you just need to reset the form using .reset() form method.
https://developer.mozilla.org/en-US/docs/Web/API/HTMLFormElement/reset
handleSubmit = (event)=>{
event.preventDefault()
....
event.target.reset()
}
render() {
return (
<>
<form onSubmit={this.handleSubmit}>
<label htmlFor='movieTitle'>Title</label>
<input name='movieTitle' id='movieTitle' type='text' />
<input type='submit' value='Find Movie Info' />
</form>
</>
)
}
I don't know if this is still relevant. But when I had similar issue this is how I resolved it.
Where you need to clear an uncontrolled form you simply do this after submission.
this.<ref-name-goes-here>.setState({value: ''});
Hope this helps.
import React, { Component } from 'react'
export default class Form extends Component {
constructor(props) {
super(props)
this.formRef = React.createRef()
this.state = {
email: '',
loading: false,
eror: null
}
}
reset = () => {
this.formRef.current.reset()
}
render() {
return (
<div>
<form>
<input type="email" name="" id=""/>
<button type="submit">Submit</button>
<button onClick={()=>this.reset()}>Reset</button>
</form>
</div>
)
}
}
/*
See newState and use of it in eventSubmit() for resetting all the state.
I have tested it is working for me. Please let me know for mistakes
*/
import React from 'react';
const newState = {
fullname: '',
email: ''
}
class Form extends React.Component {
constructor(props) {
super(props);
this.state = {
fullname: ' ',
email: ' '
}
this.eventChange = this
.eventChange
.bind(this);
this.eventSubmit = this
.eventSubmit
.bind(this);
}
eventChange(event) {
const target = event.target;
const value = target.type === 'checkbox'
? target.type
: target.value;
const name = target.name;
this.setState({[name]: value})
}
eventSubmit(event) {
alert(JSON.stringify(this.state))
event.preventDefault();
this.setState({...newState});
}
render() {
return (
<div className="container">
<form className="row mt-5" onSubmit={this.eventSubmit}>
<label className="col-md-12">
Full Name
<input
type="text"
name="fullname"
id="fullname"
value={this.state.fullname}
onChange={this.eventChange}/>
</label>
<label className="col-md-12">
email
<input
type="text"
name="email"
id="email"
value={this.state.value}
onChange={this.eventChange}/>
</label>
<input type="submit" value="Submit"/>
</form>
</div>
)
}
}
export default Form;
the easiest way is doing it regularly with just HTML and using the button type "reset" there is no need to mess with anything in react at all, no state, no nothing.
import React, {useState} from 'react'
function HowReactWorks() {
return (
<div>
<form>
<div>
<label for="name">Name</label>
<input type="text" id="name" placeholder="name" />
</div>
<div>
<label for="password">Password</label>
<input type="password" id="password" placeholder="password" />
</div>
<button type="reset">Reset</button>
<button>Submit</button>
</form>
</div>
)
}
export default HowReactWorks
edited for the people that don't know how to include HTML in react
You can use this method as well
const resetData = (e) => {
e.preventDefault();
settitle("");
setdate("");
};
<input type="text" onChange={(e) => settitle(e.target.value)} value={title} />
<input type="date" onChange={(e) => setdate(e.target.value)} value={date} />
<button onClick={resetData}>Reset Data</button>
This is the solution that worked for me, in the case of parent component triggering reset of child controlled input components:
const ParentComponent = () => {
const [reset, setReset] = useState()
const submitHandler = (e) => {
e.preventDefault()
//do your stuff
setReset(Date.now()) // pass some value to trigger update
}
return (
<form onSubmit={submitHandler}>
<ChildInputComponent reset={reset} />
<ChildInputComponent reset={reset} />
</form>
)
}
const ChildInputComponent = ({reset}) => {
const [value, setValue] = useState()
useEffect(() => {
setValue('')
}, [reset])
return <input value={value} onChange={(e) => setValue(e.target.value)} />
}
Assuming you declared
const [inputs, setInputs] = useState([]);
As multiple parameters. You can actually reset the items using this syntax:
setInputs([]);
Just in case, this how you define handleChange.
You can use this form or any ways you want.
const handleChange = (event) => {
const name = event.target.name;
const email = event.target.email;
const message = event.target.message;
const value = event.target.value;
setInputs(values => ({...values, [name]: value, [email]: value, [message]: value}))
}
You can use this form as an example.
<form onSubmit={handleSubmit}>
<div className="fields">
<div className="field half">
<label for="name">Name</label>
<input value={inputs.name || ''} type="text" name="name" id="nameId" onChange={handleChange} maxLength="30" />
</div>
<div className="field half">
<label for="email">Email</label>
<input value={inputs.email || ''} type="text" name="email" id="emailId" onChange={handleChange} maxLength="40"/>
</div>
<div className="field">
<label for="message">Message</label>
<textarea value={inputs.message || ''} name="message" id="messageId" rows="6" onChange={handleChange} maxLength="400" />
</div>
</div>
<ul className="actions">
<li><input type="submit" value="Send Message" className="primary" /></li>
<li><input onClick={resetDetails} type="reset" value="Clear" /></li>
</ul>
</form>
This is just one of many ways to declare forms. Good luck!
const onReset = () => {
form.resetFields();
};
state={
name:"",
email:""
}
handalSubmit = () => {
after api call
let resetFrom = {}
fetch('url')
.then(function(response) {
if(response.success){
resetFrom{
name:"",
email:""
}
}
})
this.setState({...resetFrom})
}
Why not use HTML-controlled items such as <input type="reset">

Submitting redux form values

I am new to react and redux technology. now started building an application that contains several redux forms. We want to submit simple form with values.
For ex: login form
Username : text input field
Password: text input field
Submit button
After entering values in fields and click on submit button i want to get the username and password field values in object or json data .. so that I can store it to my server with POST method.
Right now we are using handleSubmit(), but data is not coming as object
1 - The best practice to deal with input values are making them controlled. Which means :
Instead of
<input type='password' />
You do :
<input
type='password'
value={password}
onChange={ event => myInputHandler( event.target.value ) }
/>
The value might come from your state, redux state or as a props etc.
Your handler function differs according to where you store it.
I will give you an example with react state :
<input
type='password'
value={this.state.password}
onChange={ event => this.setState({ password : event.target.value }) }
/>
So whenever someone types, your onChange handler will be called, so that your react state will update with the input ( event.target.value ).
2 - If you need these values when a user submits, then you need to wrap these input fields within a form element and attach a onSubmit handler.
onSubmitHandler( event ){
event.preventDefault()
let password = this.state.password
// use password or other input fields, send to server etc.
}
<form onSubmit={ event => this.onSubmitHandler(event) }>
<input
type='password'
value={this.state.password}
onChange={ event => this.setState({ password : event.target.value }) }
/>
</form>
Hope you get what you need.
If you are using redux to store state then use redux-from then use redux from
import React from 'react'
import {Field, reduxForm} from 'redux-form'
const SimpleForm = props => {
const {handleSubmit, submitting} = props return (
<form onSubmit={handleSubmit(e=>console.log('your form detail here', e))}>
<div>
<label>First Name</label>
<div>
<Field name="firstName" component="input" type="text" placeholder="First Name" />
</div>
</div>
<div>
<label>Last Name</label>
<div>
<Field name="lastName" component="input" type="text" placeholder="Last Name" />
</div>
</div>
<div>
<button type="submit" disabled={pristine || submitting}>Submit</button>
</div>
</form>
) }
export default reduxForm({ form: 'simple'})(SimpleForm)
Go here for more detail
https://redux-form.com
I put the name of the input as the key that I want to use.
Then each time the input changes I destructure the event passed to the onChange function, and I use the name,value to update the state.
On form submit make sure to use preventDefault(); in order to avoid the page refreshing.
import React, { Component } from 'react'
class FormExample extends Component {
constructor(props){
super(props)
this.state = {
formData: {}
}
}
handleInputChange = ({ target: { name,value } }) => {
this.setState({
formData: {
...this.state.formData,
[name]: value
}
})
}
handleFormSubmit = e => {
e.preventDefault()
// This is your object
console.log(this.state.formData)
}
render() {
return(
<div>
<Form
handleSubmit={this.handleFormSubmit}
handleChange={this.handleInputChange}
/>
</div>
)
}
}
const Form = ({ handleSubmit, handleChange }) => (
<form onSubmit={handleSubmit}>
<input onChange={handleChange} name="username" type="text" placeholder="Username" />
<input onChange={handleChange} name="password" type="password" placeholder="Password" />
<button>Submit</button>
</form>
)
export default FormExample

Resources