Hi I have a Reactjs component in this component .I have a form inside the form i have a search field..when the user hit enter my component reloads.I want to use |prevent defaultso that mycomponentnot reloads when user hitsenter key.How to use in my code`
import React, { useState } from "react";
import data from "./info.json";
function App() {
const [searchTerm, setSearch] = useState(null);
return (
<div>
<form>
<input
type="text"
id=""
placeholder="Search"
onChange={(e) => setSearch(e.target.value)}
/>
</form>
{data
.filter((data) => {
if (searchTerm == null) {
return data;
} else if (
data.name.toLowerCase().includes(searchTerm.toLowerCase())
) {
return data;
}
})
.map((data) => (
<li>{data.name}</li>
))}
</div>
);
}
export default App;
ReactJS supports the onSubmit event by emitting synthetic events for native HTML elements.
For a <form> element, you can use the submit event to prevent the default behavior by using event.preventdefault().
You can do it in two easy steps:
Define an event handler for your form
Use the event handler to prevent form submission
import React, { useState } from "react";
import data from "./info.json";
function App() {
const [searchTerm, setSearch] = useState(null);
const fnHandleSubmit = event => {
event.preventDefault();
}
return (
<div>
<form onSubmit={fnHandleSubmit}>
<input
type="text"
id=""
placeholder="Search"
onChange={(e) => setSearch(e.target.value)}
/>
</form>
{data
.filter((data) => {
if (searchTerm == null) {
return data;
} else if (
data.name.toLowerCase().includes(searchTerm.toLowerCase())
) {
return data;
}
})
.map((data) => (
<li>{data.name}</li>
))}
</div>
);
}
export default App;
Add an onSubmit event handler on the form ,
<form onSubmit={handleOnsubmit}> </form>
in your handleOnsubmit function perfrom event.preventDefault()
function handleOnsubmit(event) {
event.preventDefault();
// Do Whatever you want
}
You will need to add preventDefault() to your form like so:
Add preventDefault() to your onSubmit event of your form:
<form onSubmit={e => e.preventDefault()}>
<input
type="text"
id=""
placeholder="Search"
onChange={e => {
setSearch(e.target.value);
}}
/>
</form>;
When clicked Enter, it triggers onSubmit(), default action is to refresh.
So to onSubmit() add preventDefault to overcome default behaviour.
Add the following line.
<form onSubmit={e => { e.preventDefault(); }}>
//code
</form>
The preventDefault() method cancels the event if it is cancelable, meaning that the default action that belongs to the event will not occur.
For example, this can be useful when:
Clicking on a "Submit" button, prevent it from submitting a form
Clicking on a link, prevent the link from following the URL
const Test = () => {
const submit = (e) => {
e.preventDefault();
console.log('I am here without refresh the form!')
}
return <form onSubmit={submit}>
<input type = 'text' ></input>
</form>
}
ReactDOM.render( <Test/> ,
document.getElementById("root")
);
<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>
<div id='root'></div>
All you need is to add e.preventDefault();
to your onSubmit function to prevent your component from reloading.
However, I'll advise you to use React UI solutions like Ant Design which provides the feature out of the box and also allow you to write your code more efficiently.
Related
const afterSubmission = (e, message) => {
e.preventDefault()
console.log(message);
if (message === "") return
displayMessage(message)
messageInput.value=""
}
<div id="message-container"></div>
<form onSubmit = {afterSubmission}>
<label for="message-input">Message</label>
<input type="text" id="message-input" />
<button type="submit" id="send-button">Send</button>
</form>
I have these two pieces of code, my question is how can I pass the value from the input tag in the form to the afterSubmission method?
Assuming this is the same component, an easy solution would be to use state.
Your code snippets aren't very useful, just as an FYI for future questions, but here's an example of me tracking form state.
import { useState } from "react";
export default function App() {
const [message, setMessage] = useState("test");
const handleChange = (e) => {
setMessage((old) => e.target.value);
};
const afterSubmission = (e) => {
e.preventDefault();
console.log(message);
};
return (
<div className="App">
<form onSubmit={afterSubmission}>
<input
type="text"
id="message-input"
value={message}
onChange={handleChange}
/>
<button
type="submit"
id="send-button"
>
Send
</button>
</form>
</div>
);
}
As you can see, this tracks your message in the component's state which makes it accessible in the afterSubmission function.
I am trying to disable a button after it is clicked, but it is not holding its disabled tag. Another weird thing is that if I click the button twice it will disable. Code below
const [loading, setLoading] = useState('Submit');
...
<form onSubmit={(event) => {
event.preventDefault();
submitBet(units, line, team, gameID);
}}>
...
<button type='submit' className='submit-betslip' id='submit-button-id'>{loading}.</button>
</form>
The loading variable is a useState. The onSubmit function:
const submitBet = async (units, line, team, id) => {
if (Number(units) === 0 && Number(line) === 0) {
console.log('Empty input');
return
}
try {
document.getElementById('submit-button-id').disabled = true;
}
...
}
Not sure if it matters but the form is within a React function. Any thoughts?
Here is a simple example to what you want to do and it's working perfectly.
import React from "react";
import "./styles.css";
export default function App() {
const [loading, setLoading] = React.useState("Submit");
const handleSubmit = (e) => {
e.preventDefault();
setLoading("Submitting..");
setTimeout(() => {
alert("submitted Successfully");
setLoading("Submit");
}, 3000);
};
return (
<div className="App">
<h1>Hello CodeSandbox</h1>
<h2>Start editing to see some magic happen!</h2>
<form onSubmit={handleSubmit}>
<input id="f1" name="f1" />
<button type="submit" disabled={loading !== "Submit"}>
{loading}.
</button>
</form>
</div>
);
}
Simply link the disable prop to the loading state.
If that is not what you want to do, just share the component with us, and I would love to help.
I am porting a JS project to React, and got stuck on form submission (using various forms in the project to update profile description, name, upload pictures etc.). The simplest/shortest one simply confirms that you wish to delete a picture that you uploaded. The API part of the project is working fine (my GET, PATCH, DELETE requests are going through), but when I press any button with type=submit, the page reloads (even though preventDefault is set).
import PopupWithForm from './PopupWithForm';
function ConfirmDeletePopup(props) {
const isLoading = props.onLoading;
function handleSubmit(e) {
e.preventDefault();
props.onSubmit(props.card)
}
return (
<PopupWithForm name={'confirm-delete-form'} title='You sure?'
isOpen={props.isOpen}
onClose={props.onClose}
onSubmit={handleSubmit}
onLoading={props.onLoading}
card={props.card}>
<fieldset className={'popup__inputs'}>
<button type="submit"
className={`popup__submit-button popup__submit-button_type_confirm-delete-form
${isLoading && '.popup__submit-button_inactive'}
popup__form-submit-button_type_confirm-delete-form`}>
{isLoading? 'Deleting...' : 'Yes'}
</button>
</fieldset>
</PopupWithForm>
)
}
export default ConfirmDeletePopup
I tried running the pressing submit with react dev tools extension open, but it didn't help. I used react dev tools extensions to double check most of the state changes (like opening the popup, and toggling the 'loading' visual state on the button etc.), which were working as intended.
And code snipets relevant to this that I have within my App.js
const [isConfirmDeletePopupOpen, setConfirmDeletePopupState] = useState(false);
const [isConfirmDeleteLoading, setConfirmDeleteLoading] = useState(false);
const [deletedCard, setDeletedCard] = useState(null);
...
function handleCardDeleteSubmit(card) {
setConfirmDeleteLoading(true);
api.deleteCard(card._id)
.then(() => {
setCards((cards) => {
return cards.filter(c => {
return c._id !== card._id
});
});
closeAllPopups();
})
.catch(err => {
console.log(err);
})
.finally(() => {
setConfirmDeleteLoading(false);
})
}
...
function handleConfirmCardDelete(card) {
setConfirmDeletePopupState(true);
setDeletedCard(card);
}
...
<ConfirmDeletePopup isOpen={isConfirmDeletePopupOpen}
onClose={closeAllPopups}
onLoading={isConfirmDeleteLoading}
card={deletedCard}
onSubmit={handleCardDeleteSubmit}/>
And PopupWithForm (in case it helps to see things more clearly).
function PopupWithForm(props) {
return (
<div className={`popup popup_type_${props.name} ${props.isOpen? 'popup_opened':''}`}>
<div className="popup__container">
<button type="button"
onClick={props.onClose}
className={`popup__close-button popup__close-button_type_${props.name}`}
aria-label={`close${props.title}`}>{}</button>
<form className={`edit-form popup__form popup__form_type_${props.name}`}
name={props.name}
id={props.name}
noValidate>
<h2 className={`popup__heading ${props.name === 'update-avatar-form'?
'popup__form-heading_type_update-avatar-form': ''}`}>{props.title}</h2>
{props.children}
</form>
</div>
</div>
)
}
export default PopupWithForm;
Quentin was right, when I was refactoring my PopupWithForm I did not pass it the onSubmit hook, which is why the page was reloading on form submission.
The fixed version:
<form className={`edit-form popup__form popup__form_type_${props.name}`}
onSubmit={props.onSubmit}
name={props.name}
id={props.name}
noValidate>
<h2 className={`popup__heading ${props.name === 'update-avatar-form'?
'popup__form-heading_type_update-avatar-form': ''}`}>{props.title}</h2>
{props.children}
</form>
Do you tried to wrapping your component in a tag form?
const handleSubmit = (e) => {
e.preventDefault();
}
<form submit={handleSubmit}>
<button type="submit">Send</button>
</form>
I have two buttons on a page and based on a state in that component, a particular button should be displayed, I have tried for hours, still not working
Here is my code
const App = () =>{
const [edit,setEdit] = useState(false)
const updateUser =() =>{
//update action
setEdit(false)
}
return(
<div>
<form>
<input type="text"/>
<input type="text"/>
{edit ? (<button onClick={()=>updateUser()}>Save</button>) : (<button onClick={()=>{setEdit(true)}}>Edit</button>)}
</form>
</div>
)
}
export default App;
when the page loads the button shows Edit, but after clicking, i expect it to change to save since edit is now true, but it still remains same
you have a side effect in this situation caused by edit so you should make use of good old pal useEffect also those prevenDefaults will prevent your form from refreshing and are necessary. I made a livedemo at codeSandbox and here is the code itself:
import React, { useState, useEffect } from "react";
const App = () => {
const [edit, setEdit] = useState(false);
const updateUser = (e) => {
e.preventDefault();
//update action
setEdit(false);
};
const editUser = (e) => {
e.preventDefault();
//stuffs you wanna do for editing
setEdit(true);
};
useEffect(() => {}, [edit]);
return (
<div>
<form onSubmit={(e) => updateUser(e)}>
<input type="text" />
<input type="text" />
{edit ? (
<button type="submit">Save</button>
) : (
<button onClick={(e) => editUser(e)}>Edit</button>
)}
</form>
</div>
);
};
export default App;
P.S: Although it works, I don't approve of the approach
You can try this approach also, Here I used e.preventDefault on the event when submitting the form to prevent a browser reload/refresh.
const App = () =>{
const [edit,setEdit] = useState(false)
const updateUser =(e) =>{
//update action
e.preventDefault();
setEdit(!edit);
}
return(
<div>
<form>
<input type="text"/>
<input type="text"/>
{edit ? (<button onClick={updateUser}>Save</button>) :
(<button onClick={updateUser}>Edit</button>)}
</form>
</div>
)
}
export default App;
Not need to using useEffect just check if edit is true or not !
EDIT : I made it this way so u can see what happend and i think u should learn more about react and hooks , i prefer watching youtube!
const App = () => {
const [edit, setEdit] = React.useState(true);
const clickHandler =(e)=>{
e.preventDefault();
if(!edit){
// update user information here not need to make
// different function and state or somthing else.
console.log("updateUser")
}
setEdit(prev=>!prev);
}
return(
<div>
<form>
<input type="text"/>
<input type="text"/>
<button onClick={clickHandler} disabled={!edit}>Edit</button>
<button onClick={clickHandler} disabled={edit}>Save</button>
</form>
</div>
)
}
ReactDOM.render(<App />, document.getElementById("react"));
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.8.4/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.8.4/umd/react-dom.production.min.js"></script>
<div id="react"></div>
Issue
As I see it, your issue is that the buttons don't have a type specified to them, so they actually inherit an initial value of type="submit" and this causes your form to take the default submit action and reload the page. You likely aren't seeing this reload as it may be occurring very quickly.
type
The default behavior of the button. Possible values are:
submit: The button submits the form data to the server. This is the default if the attribute is not specified for buttons associated
with a <form>, or if the attribute is an empty or invalid value.
reset: The button resets all the controls to their initial values, like <input type="reset">. (This behavior tends to annoy users.)
button: The button has no default behavior, and does nothing when pressed by default. It can have client-side scripts listen to the
element's events, which are triggered when the events occur.
Solution
Provide/specify the button types to not be "submit and valid, i.e. use type="button".
const App = () => {
const [edit, setEdit] = React.useState(false);
const updateUser = () => {
//update action
setEdit(false);
};
return (
<div>
<form>
<input type="text" />
<input type="text" />
{edit ? (
<button type="button" onClick={updateUser}>
Save
</button>
) : (
<button
type="button"
onClick={() => {
setEdit(true);
}}
>
Edit
</button>
)}
</form>
</div>
);
};
Here is an example that also, IMO, make the code a bit more DRY.
const App = () => {
const [edit, setEdit] = React.useState(false);
const updateUser = () => {
//update action
setEdit(false);
};
return (
<div>
<form>
<input type="text" />
<input type="text" />
<button
type="button"
onClick={() => {
edit ? updateUser() : setEdit(true);
}}
>
{edit ? "Save" : "Edit"}
</button>
</form>
</div>
);
};
Demo
I would like to prevent my application to prevent adding empty task. Following the code which adds new task in an array. May I ask please how to put condition to prevent adding empty task?
The application is built on Mozilla's guideline for the react app.
import React, {useState} from 'react';
function Form(props){
const [name, setName ] = useState('');
const [important, setImportant] = useState(false);
function handleChangeImportant(e){
console.log(e);
e.preventDefault();
setImportant(e.target.checked);
};
function handleChange(e) {
setName(e.target.value);
}
function handleSubmit(e){
e.preventDefault();
//alert('Moin');
props.addTask(name);
setName("");
}
return(
<form onSubmit={handleSubmit}>
<h2 className="label-wrapper">
<label htmlFor="new-todo-input" className="label__lg">
What needs to be done?
</label>
</h2>
<input
type="text"
id="new-todo-input"
className="input input__lg"
name="text"
autoComplete="off"
value={name}
onChange={handleChange}
/>
<input
type="checkbox"
id="todo-0"
value={important}
onChange={handleChangeImportant}
/> Important
<button type = "submit" className="btn btn__primary btn__lg">
Add
</button>
</form>
);
}
export default Form;
```
Check if name is not empty.
function handleSubmit(e){
e.preventDefault();
//alert('Moin');
if(name !==''){
props.addTask(name);
setName("");
}
}
function handleSubmit(e) {
e.preventDefault();
if (name === '') return;
props.addTask(name);
setName('');
}