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Prevent form submission on Enter key press

I have a form with two text boxes, one select drop down and one radio button. When the enter key is pressed, I want to call my JavaScript function, but when I press it, the form is submitted.

How do I prevent the form from being submitted when the enter key is pressed?


J
John Slegers
if(characterCode == 13) {
    // returning false will prevent the event from bubbling up.
    return false; 
} else{
    return true;
}

Ok, so imagine you have the following textbox in a form:

<input id="scriptBox" type="text" onkeypress="return runScript(event)" />

In order to run some "user defined" script from this text box when the enter key is pressed, and not have it submit the form, here is some sample code. Please note that this function doesn't do any error checking and most likely will only work in IE. To do this right you need a more robust solution, but you will get the general idea.

function runScript(e) {
    //See notes about 'which' and 'key'
    if (e.keyCode == 13) {
        var tb = document.getElementById("scriptBox");
        eval(tb.value);
        return false;
    }
}

returning the value of the function will alert the event handler not to bubble the event any further, and will prevent the keypress event from being handled further.

NOTE:

It's been pointed out that keyCode is now deprecated. The next best alternative which has also been deprecated.

Unfortunately the favored standard key, which is widely supported by modern browsers, has some dodgy behavior in IE and Edge. Anything older than IE11 would still need a polyfill.

Furthermore, while the deprecated warning is quite ominous about keyCode and which, removing those would represent a massive breaking change to untold numbers of legacy websites. For that reason, it is unlikely they are going anywhere anytime soon.


Is this a situation where PreventDefualt can be used?
Yes, instead of the return false.
Instead of eval, you could build an array of the valid functions, then use .indexOf() to check whether the user's input is in that array, and call the function if it is. Reduces scope for errors/users screwing up.
While I agree with your note about keyCode and which being deprecated, I think developers should help make that transition by not supporting such legacy browsers, especially now that IE is officially dead and Edge has adopted Chromium. Anyway, a nice tool to inspect the different identifiers keys have is keyjs.dev
B
Bradley4

Use both event.which and event.keyCode:

function (event) {
    if (event.which == 13 || event.keyCode == 13) {
        //code to execute here
        return false;
    }
    return true;
};

Why both event.which and event.keyCode?
Some browsers support which others support keyCode. It is good practice to include both.
Also use the keydown event instead of keyup or keypress
@Agiagnoc but what event should this be attached to ?
@manish, keypress gives you more information to play with than keydown/up. stackoverflow.com/a/9905293/322537
G
Gibolt

event.key === "Enter"

More recent and much cleaner: use event.key. No more arbitrary number codes!

NOTE: The old properties (.keyCode and .which) are Deprecated.

const node = document.getElementsByClassName("mySelect")[0];
node.addEventListener("keydown", function(event) {
    if (event.key === "Enter") {
        event.preventDefault();
        // Do more work
    }
});

Modern style, with lambda and destructuring

node.addEventListener("keydown", ({key}) => {
    if (key === "Enter") // Handle press
})

Mozilla Docs

Supported Browsers


isn't this just a macro or alias? is there any benefit in terms of performance by using this code?
keyCode is deprecated. This is more readable and maintainable than a magic integer in your code
For those wondering how to find the key value for different keys, you can use keyjs.dev
In 2021, I believe this is the correct answer.
Readable, yes! Cleaner? 13 is more clean than Enter. There was no questions like, is it "Enter" or "enter". If you can remember "Enter", you can always remember 13. It takes less room.
M
Matt K

If you're using jQuery:

$('input[type=text]').on('keydown', function(e) {
    if (e.which == 13) {
        e.preventDefault();
    }
});

keyup is fired AFTER the submission, and can't therefore cancel it.
U
Umer Qureshi

Detect Enter key pressed on whole document:

$(document).keypress(function (e) {
    if (e.which == 13) {
        alert('enter key is pressed');
    }
});

http://jsfiddle.net/umerqureshi/dcjsa08n/3/


S
Shyju

Override the onsubmit action of the form to be a call to your function and add return false after it, ie:

<form onsubmit="javascript:myfunc();return false;" >

I cant override onsubmit as i have another form submit in this page
yes you can. Javascript is prototype based language. document.forms["form_name"].onsubmit = fucntion() {}
I have another delete procedure to run when the form is submitted.So i want to maintain as it is
@Shyju if you want to run both: the action defined in the form tag and also the javascript triggered when pressing the submit button, you can just remove the code return false;, then both action will be triggered.
c
caffeinescript

A react js solution

 handleChange: function(e) {
    if (e.key == 'Enter') {
      console.log('test');
    }


 <div>
    <Input type="text"
       ref = "input"
       placeholder="hiya"
       onKeyPress={this.handleChange}
    />
 </div>

M
Matt Doran

So maybe the best solution to cover as many browsers as possible and be future proof would be

if (event.which === 13 || event.keyCode === 13 || event.key === "Enter")

s
snnsnn

Here is how you can do it using JavaScript:

//in your **popup.js** file just use this function var input = document.getElementById("textSearch"); input.addEventListener("keyup", function(event) { event.preventDefault(); if (event.keyCode === 13) { alert("yes it works,I'm happy "); } });


H
Hitesh Sahu

Below code will add listener for ENTER key on entire page.

This can be very useful in screens with single Action button eg Login, Register, Submit etc.

<head>
        <!--Import jQuery IMPORTANT -->
        <script src="https://code.jquery.com/jquery-2.1.1.min.js"></script>

         <!--Listen to Enter key event-->
        <script type="text/javascript">

            $(document).keypress(function (e) {
                if (e.which == 13 || event.keyCode == 13) {
                    alert('enter key is pressed');
                }
            });
        </script>
    </head>

Tested on all browsers.


c
chim

A jQuery solution.

I came here looking for a way to delay the form submission until after the blur event on the text input had been fired.

$(selector).keyup(function(e){
  /*
   * Delay the enter key form submit till after the hidden
   * input is updated.
   */

  // No need to do anything if it's not the enter key
  // Also only e.which is needed as this is the jQuery event object.
  if (e.which !== 13) {
       return;
  }

  // Prevent form submit
  e.preventDefault();

  // Trigger the blur event.
  this.blur();

  // Submit the form.
  $(e.target).closest('form').submit();
});

Would be nice to get a more general version that fired all the delayed events rather than just the form submit.


T
Thanos

A much simpler and effective way from my perspective should be :

function onPress_ENTER()
{
        var keyPressed = event.keyCode || event.which;

        //if ENTER is pressed
        if(keyPressed==13)
        {
            alert('enter pressed');
            keyPressed=null;
        }
        else
        {
            return false;
        }
}

C
Community

A little simple

Don't send the form on keypress "Enter":

<form id="form_cdb" onsubmit="return false">

Execute the function on keypress "Enter":

<input type="text" autocomplete="off" onkeypress="if(event.key === 'Enter') my_event()">

W
Wagner Pereira

Using TypeScript, and avoid multiples calls on the function

let el1= <HTMLInputElement>document.getElementById('searchUser');
el1.onkeypress = SearchListEnter;

function SearchListEnter(event: KeyboardEvent) {
    if (event.which !== 13) {
        return;
    }
    // more stuff
}

This question is more than eight years old. Typescript did not exist then. So are you sure you're not answering an other question?
M
Mizanur Rahaman
<div class="nav-search" id="nav-search">
        <form class="form-search">
            <span class="input-icon">
                <input type="text" placeholder="Search ..." class="nav-search-input" id="search_value" autocomplete="off" />
                <i class="ace-icon fa fa-search nav-search-icon"></i>
            </span>
            <input type="button" id="search" value="Search" class="btn btn-xs" style="border-radius: 5px;">
        </form>

</div>

<script type="text/javascript">
    $("#search_value").on('keydown', function(e) {
        if (e.which == 13) {
             $("#search").trigger('click');
            return false;
        }
    });
    $("#search").on('click',function(){
        alert('You press enter');
    });
</script>

x
xgqfrms

native js (fetch api)

document.onload = (() => { alert('ok'); let keyListener = document.querySelector('#searchUser'); // keyListener.addEventListener('keypress', (e) => { if(e.keyCode === 13){ let username = e.target.value; console.log(`username = ${username}`); fetch(`https://api.github.com/users/${username}`,{ data: { client_id: 'xxx', client_secret: 'xxx' } }) .then((user)=>{ console.log(`user = ${user}`); }); fetch(`https://api.github.com/users/${username}/repos`,{ data: { client_id: 'xxx', client_secret: 'xxx' } }) .then((repos)=>{ console.log(`repos = ${repos}`); for (let i = 0; i < repos.length; i++) { console.log(`repos ${i} = ${repos[i]}`); } }); }else{ console.log(`e.keyCode = ${e.keyCode}`); } }); })();


Why has client_id etc been included here? Is the code legit?
A
Akhilesh Singh
<form id="form1" runat="server" onkeypress="return event.keyCode != 13;">

Add this Code In Your HTML Page...it will disable ...Enter Button..


T
Tobi Obeck

Cross Browser Solution

Some older browsers implemented keydown events in a non-standard way.

KeyBoardEvent.key is the way it is supposed to be implemented in modern browsers.

which and keyCode are deprecated nowadays, but it doesn't hurt to check for these events nonetheless so that the code works for users that still use older browsers like IE.

The isKeyPressed function checks if the pressed key was enter and event.preventDefault() hinders the form from submitting.

  if (isKeyPressed(event, 'Enter', 13)) {
    event.preventDefault();
    console.log('enter was pressed and is prevented');
  }

Minimal working example

JS

function isKeyPressed(event, expectedKey, expectedCode) {
  const code = event.which || event.keyCode;

  if (expectedKey === event.key || code === expectedCode) {
    return true;
  }
  return false;
}

document.getElementById('myInput').addEventListener('keydown', function(event) {
  if (isKeyPressed(event, 'Enter', 13)) {
    event.preventDefault();
    console.log('enter was pressed and is prevented');
  }
});

HTML

<form>
  <input id="myInput">
</form>

https://jsfiddle.net/tobiobeck/z13dh5r2/


K
Kamil Kiełczewski

Use event.preventDefault() inside user defined function

<form onsubmit="userFunction(event)"> ...

function userFunction(ev) { if(!event.target.send.checked) { console.log('form NOT submit on "Enter" key') ev.preventDefault(); } } Open chrome console> network tab to see


submit on enter


s
sobelito

I used document on, which covers dynamically added html after page load:

  $(document).on('keydown', '.selector', function (event) {
    if (event.which == 13 || event.keyCode == 13) {
      //do your thang
    }
  });

Added updates from @Bradley4


Only works if you install jquery.