Develop Reference

how to detect what the user have typed in input box in html & javascript

I want my input box to detect a text like this...
var input = document.getElemntById("inputbox");
function buttonclick() {
if ((input = "h")) {
input.innerHTML = "hello";
}
}
This is by button click but i need to do this onkeyup() but I don't know how to..
if the user type h the input box suddenly make it hello
how do I do this?
Thanks in advance.

You really just need an onkeyup event on your html tag.
var input = document.getElementById("inputbox");
function buttonclick() {
if (input.value === "h") {
input.value = "hello";
}
}
<input id="inputbox" onkeyup="buttonclick()">
When the key is lifted the function buttonclick() is called. You also need to grab the value of the input as the innerHTML does not refer to what is placed within the input box but rather the actual code that would be between lets say two <div> </div> tags.

Add a eventListener:
document.getElementById("inputbox").addEventListener("keyup", (e) => {
if (e.target.value == "h") e.target.value = "hello"
}

You have to do following changes to work:
1) TYPO: You should use getElementById instead of getElemntById
var input = document.getElementById("inputbox");
2) You can use keyup event as
input.addEventListener( "keyup", changeInputValue )
3) When you are checking equality of two string, use ===. = is for assignment.
input.value.trim() === "h"
4) You have to compare the value of the input with h.
input.value.trim() === "h"
NOTE: I've used trim method because if user added some space
before h then it will still set hello. You can remove it if you
don't want.
var input = document.getElementById("inputbox");
function changeInputValue() {
if (input.value.trim() === "h") { // input.value === "h"
input.value = "hello";
}
}
input.addEventListener("keyup", changeInputValue)
<input type="text" id="inputbox" />

javascript how to return a value from event function to outer function

Can someone please help me with this. I what to return var from input event function to outer function.
function takeInputText() {
var input = document.getElementById('inputText')
var newText;
input.onkeyup = function(e) {
var text = input.value;
if ( e.which == 13 ) {
newText = text;
input.value = '';
//return newText - I want to return 'newText' to 'takeInputText()' so i can
// use 'takeInputText()' as a variable
}
}
}
takeInputText();

If you are willing to play with the value of the input once user hit enter key, bind keyup event over input and manipulate the value in the callback function.
You can also call another function in which value of the input could be passed.
Example:
var input = document.getElementById('inputText');
input.onkeyup = function(e) {
var code = e.which || e.keyCode;
if (code == 13) {
appendInput(this.value);
this.value = '';
}
}
function appendInput(value) {
var elem = document.createElement('h2');
elem.textContent = value;
document.getElementById('preview').appendChild(elem);
}
<input type="text" id="inputText">
<div id="preview"></div>

You cannot use takeInputText() as a variable since what you are doing inside takeInputText is just attaching a keyup listener to the input element and the function returns immediately (undefined is returned in this case).
To make use of the value, pass the variable as an argument to a function that you want to invoke when the condition inside the handler is true, for example:
input.onkeyup = function(e) {
var text = input.value;
if ( e.which == 13 ) {
input.value = '';
yourFunction(text);
}
}

Prevent jumping to the second row after pressing Enter on a text area

I have a <textarea> that onkeypress ('Enter') sends a message in a live chat. The problem is that after pressing first time "Enter", the textarea field starts from the second input row.
How do I make the field reset or not taking "Enter" as a next row value?
Code:
<textarea disabled = "enabled"
onblur = "stopTyping();"
onfocus = "playTitleFlag=false;
window.title='';"
onkeypress = "tryToSend(event);"
id = "chatmsg"
rows = "1"
cols = "1"
class = "chatmsg"></textarea>
And the onkeypress function:
function tryToSend(event) {
var key = event.keyCode;
if (key == "13") {
sendMsg();
return;
}
var msg = document.getElementById("chatmsg").value;
if (trim(msg) != "") {
typing();
}
else {
stopTyping();
}
}

To cancel the default behaviour you should use return false;
see What's the effect of adding 'return false' to a click event listener?
To reset a textarea simply set its value to "". document.getElementById(f).value = "";
P.S
Note that event.keyCode return an integer

to make that input text field holds focus and not to lose when I click on something else (to focus always be on input with id="input_message")?

I made simple web chat, bubles ( messages) above one text field (input message) and send button. How to make that input text field holds focus and not to lose when I click on something else (to focus always be on input with id="input_message") ?

var el = document.getElementById('input_message');
el.focus();
el.onblur = function () {
setTimeout(function () {
el.focus();
});
};
Here's the fiddle: http://jsfiddle.net/MwaNM/

Here's a dirty hack.
<input type="text" id="input_message" />
<script type="text/javascript">
with (document.getElementById('input_message')) {
onblur = function(e) {
var elm = e.target;
setTimeout(function(){elm.focus()});
}
onkeydown = function(e) {
var key = e.which || e.keyCode;
if (key == 9) e.preventDefault();
// code for tab is 9
}
}
</script>

var inputElement = document.getElementById("input_message");
inputElement.focus();
inputElement.addEventListener("blur", function(event){
inputElement.focus();
});
http://jsfiddle.net/653w1mpv/

Enter key press behaves like a Tab in Javascript

I'm looking to create a form where pressing the enter key causes focus to go to the "next" form element on the page. The solution I keep finding on the web is...
<body onkeydown="if(event.keyCode==13){event.keyCode=9; return event.keyCode}">
Unfortunately, that only seems to work in IE. So the real meat of this question is if anybody knows of a solution that works for FF and Chrome? Additionally, I'd rather not have to add onkeydown events to the form elements themselves, but if that's the only way, it will have to do.
This issue is similar to question 905222, but deserving of it's own question in my opinion.
Edit: also, I've seen people bring up the issue that this isn't good style, as it diverges from form behavior that users are used to. I agree! It's a client request :(

I used the logic suggested by Andrew which is very effective. And this is my version:
$('body').on('keydown', 'input, select', function(e) {
if (e.key === "Enter") {
var self = $(this), form = self.parents('form:eq(0)'), focusable, next;
focusable = form.find('input,a,select,button,textarea').filter(':visible');
next = focusable.eq(focusable.index(this)+1);
if (next.length) {
next.focus();
} else {
form.submit();
}
return false;
}
});
KeyboardEvent's keycode (i.e: e.keycode) depreciation notice :- https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/keyCode

The simplest vanilla JS snippet I came up with:
document.addEventListener('keydown', function (event) {
if (event.keyCode === 13 && event.target.nodeName === 'INPUT') {
var form = event.target.form;
var index = Array.prototype.indexOf.call(form, event.target);
form.elements[index + 1].focus();
event.preventDefault();
}
});
Works in IE 9+ and modern browsers.

Map [Enter] key to work like the [Tab] key
I've rewritten Andre Van Zuydam's answer, which didn't work for me, in jQuery. This caputures both Enter and Shift+Enter. Enter tabs forward, and Shift+Enter tabs back.
I've also rewritten the way self is initialized by the current item in focus. The form is also selected that way. Here's the code:
// Map [Enter] key to work like the [Tab] key
// Daniel P. Clark 2014
// Catch the keydown for the entire document
$(document).keydown(function(e) {
// Set self as the current item in focus
var self = $(':focus'),
// Set the form by the current item in focus
form = self.parents('form:eq(0)'),
focusable;
// Array of Indexable/Tab-able items
focusable = form.find('input,a,select,button,textarea,div[contenteditable=true]').filter(':visible');
function enterKey(){
if (e.which === 13 && !self.is('textarea,div[contenteditable=true]')) { // [Enter] key
// If not a regular hyperlink/button/textarea
if ($.inArray(self, focusable) && (!self.is('a,button'))){
// Then prevent the default [Enter] key behaviour from submitting the form
e.preventDefault();
} // Otherwise follow the link/button as by design, or put new line in textarea
// Focus on the next item (either previous or next depending on shift)
focusable.eq(focusable.index(self) + (e.shiftKey ? -1 : 1)).focus();
return false;
}
}
// We need to capture the [Shift] key and check the [Enter] key either way.
if (e.shiftKey) { enterKey() } else { enterKey() }
});
The reason textarea
is included is because we "do" want to tab into it. Also, once in, we don't want to stop the default behavior of Enter from putting in a new line.
The reason a and button
allow the default action, "and" still focus on the next item, is because they don't always load another page. There can be a trigger/effect on those such as an accordion or tabbed content. So once you trigger the default behavior, and the page does its special effect, you still want to go to the next item since your trigger may have well introduced it.

Thank you for the good script.
I have just added the shift event on the above function to go back between elements, I thought someone may need this.
$('body').on('keydown', 'input, select, textarea', function(e) {
var self = $(this)
, form = self.parents('form:eq(0)')
, focusable
, next
, prev
;
if (e.shiftKey) {
if (e.keyCode == 13) {
focusable = form.find('input,a,select,button,textarea').filter(':visible');
prev = focusable.eq(focusable.index(this)-1);
if (prev.length) {
prev.focus();
} else {
form.submit();
}
}
}
else
if (e.keyCode == 13) {
focusable = form.find('input,a,select,button,textarea').filter(':visible');
next = focusable.eq(focusable.index(this)+1);
if (next.length) {
next.focus();
} else {
form.submit();
}
return false;
}
});

This worked for me:
$(document).on('keydown', ':tabbable', function(e) {
if (e.key === "Enter") {
e.preventDefault();
var $canfocus = $(':tabbable:visible');
var index = $canfocus.index(document.activeElement) + 1;
if (index >= $canfocus.length) index = 0;
$canfocus.eq(index).focus();
}
});

Changing this behaviour actually creates a far better user experience than the default behaviour implemented natively. Consider that the behaviour of the enter key is already inconsistent from the user's point of view, because in a single line input, enter tends to submit a form, while in a multi-line textarea, it simply adds a newline to the contents of the field.
I recently did it like this (uses jQuery):
$('input.enterastab, select.enterastab, textarea.enterastab').live('keydown', function(e) {
if (e.keyCode==13) {
var focusable = $('input,a,select,button,textarea').filter(':visible');
focusable.eq(focusable.index(this)+1).focus();
return false;
}
});
This is not terribly efficient, but works well enough and is reliable - just add the 'enterastab' class to any input element that should behave in this way.

I reworked the OPs solution into a Knockout binding and thought I'd share it. Thanks very much :-)
Here's a Fiddle
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js" type="text/javascript"></script>
<script src="http://ajax.aspnetcdn.com/ajax/knockout/knockout-2.2.1.js" type="text/javascript"></script>
</head>
<body>
<div data-bind="nextFieldOnEnter:true">
<input type="text" />
<input type="text" />
<select>
<option value="volvo">Volvo</option>
<option value="saab">Saab</option>
<option value="mercedes">Mercedes</option>
<option value="audi">Audi</option>
</select>
<input type="text" />
<input type="text" />
</div>
<script type="text/javascript">
ko.bindingHandlers.nextFieldOnEnter = {
init: function(element, valueAccessor, allBindingsAccessor) {
$(element).on('keydown', 'input, select', function (e) {
var self = $(this)
, form = $(element)
, focusable
, next
;
if (e.keyCode == 13) {
focusable = form.find('input,a,select,button,textarea').filter(':visible');
var nextIndex = focusable.index(this) == focusable.length -1 ? 0 : focusable.index(this) + 1;
next = focusable.eq(nextIndex);
next.focus();
return false;
}
});
}
};
ko.applyBindings({});
</script>
</body>
</html>

Here is an angular.js directive to make enter go to the next field using the other answers as inspiration. There is some, perhaps, odd looking code here because I only use the jQlite packaged with angular. I believe most of the features here work in all browsers > IE8.
angular.module('myapp', [])
.directive('pdkNextInputOnEnter', function() {
var includeTags = ['INPUT', 'SELECT'];
function link(scope, element, attrs) {
element.on('keydown', function (e) {
// Go to next form element on enter and only for included tags
if (e.keyCode == 13 && includeTags.indexOf(e.target.tagName) != -1) {
// Find all form elements that can receive focus
var focusable = element[0].querySelectorAll('input,select,button,textarea');
// Get the index of the currently focused element
var currentIndex = Array.prototype.indexOf.call(focusable, e.target)
// Find the next items in the list
var nextIndex = currentIndex == focusable.length - 1 ? 0 : currentIndex + 1;
// Focus the next element
if(nextIndex >= 0 && nextIndex < focusable.length)
focusable[nextIndex].focus();
return false;
}
});
}
return {
restrict: 'A',
link: link
};
});
Here's how I use it in the app I'm working on, by just adding the pdk-next-input-on-enter directive on an element. I am using a barcode scanner to enter data into fields, the default function of the scanner is to emulate a keayboard, injecting an enter key after typing the data of the scanned barcode.
There is one side-effect to this code (a positive one for my use-case), if it moves focus onto a button, the enter keyup event will cause the button's action to be activated. This worked really well for my flow as the last form element in my markup is a button that I want activated once all the fields have been "tabbed" through by scanning barcodes.
<!DOCTYPE html>
<html ng-app=myapp>
<head>
<script src="angular.min.js"></script>
<script src="controller.js"></script>
</head>
<body ng-controller="LabelPrintingController">
<div class='.container' pdk-next-input-on-enter>
<select ng-options="p for p in partNumbers" ng-model="selectedPart" ng-change="selectedPartChanged()"></select>
<h2>{{labelDocument.SerialNumber}}</h2>
<div ng-show="labelDocument.ComponentSerials">
<b>Component Serials</b>
<ul>
<li ng-repeat="serial in labelDocument.ComponentSerials">
{{serial.name}}<br/>
<input type="text" ng-model="serial.value" />
</li>
</ul>
</div>
<button ng-click="printLabel()">Print</button>
</div>
</body>
</html>

Try this...
$(document).ready(function () {
$.fn.enterkeytab = function () {
$(this).on('keydown', 'input,select,text,button', function (e) {
var self = $(this)
, form = self.parents('form:eq(0)')
, focusable
, next
;
if (e.keyCode == 13) {
focusable = form.find('input,a,select').filter(':visible');
next = focusable.eq(focusable.index(this) + 1);
if (next.length) {
//if disable try get next 10 fields
if (next.is(":disabled")){
for(i=2;i<10;i++){
next = focusable.eq(focusable.index(this) + i);
if (!next.is(":disabled"))
break;
}
}
next.focus();
}
return false;
}
});
}
$("form").enterkeytab();
});

I've had a similar problem, where I wanted to press + on the numpad to tab to the next field. Now I've released a library that I think will help you.
PlusAsTab: A jQuery plugin to use the numpad plus key as a tab key equivalent.
Since you want enter/↵ instead, you can set the options. Find out which key you want to use with the jQuery event.which demo.
JoelPurra.PlusAsTab.setOptions({
// Use enter instead of plus
// Number 13 found through demo at
// https://api.jquery.com/event.which/
key: 13
});
// Matches all inputs with name "a[]" (needs some character escaping)
$('input[name=a\\[\\]]').plusAsTab();
You can try it out yourself in the PlusAsTab enter as tab demo.

function return2tab (div)
{
document.addEventListener('keydown', function (ev) {
if (ev.key === "Enter" && ev.target.nodeName === 'INPUT') {
var focusableElementsString = 'a[href], area[href], input:not([disabled]), select:not([disabled]), textarea:not([disabled]), button:not([disabled]), iframe, object, embed, [tabindex="0"], [contenteditable]';
let ol= div.querySelectorAll(focusableElementsString);
for (let i=0; i<ol.length; i++) {
if (ol[i] === ev.target) {
let o= i<ol.length-1? ol[i+1]: o[0];
o.focus(); break;
}
}
ev.preventDefault();
}
});
}

I have it working in only JavaScript. Firefox won't let you update the keyCode, so all you can do is trap keyCode 13 and force it to focus on the next element by tabIndex as if keyCode 9 was pressed. The tricky part is finding the next tabIndex. I have tested this only on IE8-IE10 and Firefox and it works:
function ModifyEnterKeyPressAsTab(event)
{
var caller;
var key;
if (window.event)
{
caller = window.event.srcElement; //Get the event caller in IE.
key = window.event.keyCode; //Get the keycode in IE.
}
else
{
caller = event.target; //Get the event caller in Firefox.
key = event.which; //Get the keycode in Firefox.
}
if (key == 13) //Enter key was pressed.
{
cTab = caller.tabIndex; //caller tabIndex.
maxTab = 0; //highest tabIndex (start at 0 to change)
minTab = cTab; //lowest tabIndex (this may change, but start at caller)
allById = document.getElementsByTagName("input"); //Get input elements.
allByIndex = []; //Storage for elements by index.
c = 0; //index of the caller in allByIndex (start at 0 to change)
i = 0; //generic indexer for allByIndex;
for (id in allById) //Loop through all the input elements by id.
{
allByIndex[i] = allById[id]; //Set allByIndex.
tab = allByIndex[i].tabIndex;
if (caller == allByIndex[i])
c = i; //Get the index of the caller.
if (tab > maxTab)
maxTab = tab; //Get the highest tabIndex on the page.
if (tab < minTab && tab >= 0)
minTab = tab; //Get the lowest positive tabIndex on the page.
i++;
}
//Loop through tab indexes from caller to highest.
for (tab = cTab; tab <= maxTab; tab++)
{
//Look for this tabIndex from the caller to the end of page.
for (i = c + 1; i < allByIndex.length; i++)
{
if (allByIndex[i].tabIndex == tab)
{
allByIndex[i].focus(); //Move to that element and stop.
return;
}
}
//Look for the next tabIndex from the start of page to the caller.
for (i = 0; i < c; i++)
{
if (allByIndex[i].tabIndex == tab + 1)
{
allByIndex[i].focus(); //Move to that element and stop.
return;
}
}
//Continue searching from the caller for the next tabIndex.
}
//The caller was the last element with the highest tabIndex,
//so find the first element with the lowest tabIndex.
for (i = 0; i < allByIndex.length; i++)
{
if (allByIndex[i].tabIndex == minTab)
{
allByIndex[i].focus(); //Move to that element and stop.
return;
}
}
}
}
To use this code, add it to your html input tag:
<input id="SomeID" onkeydown="ModifyEnterKeyPressAsTab(event);" ... >
Or add it to an element in javascript:
document.getElementById("SomeID").onKeyDown = ModifyEnterKeyPressAsTab;
A couple other notes:
I only needed it to work on my input elements, but you could extend it to other document elements if you need to. For this, getElementsByClassName is very helpful, but that is a whole other topic.
A limitation is that it only tabs between the elements that you have added to your allById array. It does not tab around to the other things that your browser might, like toolbars and menus outside your html document. Perhaps this is a feature instead of a limitation. If you like, trap keyCode 9 and this behavior will work with the tab key too.

You can use my code below, tested in Mozilla, IE, and Chrome
// Use to act like tab using enter key
$.fn.enterkeytab=function(){
$(this).on('keydown', 'input, select,', function(e) {
var self = $(this)
, form = self.parents('form:eq(0)')
, focusable
, next
;
if (e.keyCode == 13) {
focusable = form.find('input,a,select,button').filter(':visible');
next = focusable.eq(focusable.index(this)+1);
if (next.length) {
next.focus();
} else {
alert("wd");
//form.submit();
}
return false;
}
});
}
How to Use?
$("#form").enterkeytab(); // enter key tab

If you can I would reconsider doing this: the default action of pressing <Enter> while in a form submits the form and anything you do to change this default action / expected behaviour could cause some usability issues with the site.

Vanilla js with support for Shift + Enter and ability to choose which HTML tags are focusable. Should work IE9+.
onKeyUp(e) {
switch (e.keyCode) {
case 13: //Enter
var focusableElements = document.querySelectorAll('input, button')
var index = Array.prototype.indexOf.call(focusableElements, document.activeElement)
if(e.shiftKey)
focus(focusableElements, index - 1)
else
focus(focusableElements, index + 1)
e.preventDefault()
break;
}
function focus(elements, index) {
if(elements[index])
elements[index].focus()
}
}

Here's what I came up with.
form.addEventListener("submit", (e) => { //On Submit
let key = e.charCode || e.keyCode || 0 //get the key code
if (key = 13) { //If enter key
e.preventDefault()
const inputs = Array.from(document.querySelectorAll("form input")) //Get array of inputs
let nextInput = inputs[inputs.indexOf(document.activeElement) + 1] //get index of input after the current input
nextInput.focus() //focus new input
}
}

Many answers here uses e.keyCode and e.which that are deprecated.
Instead you should use e.key === 'Enter'.
Documentation: https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/keyCode
I'm sorry but I can't test these snippets just now. Will come back later after testing it.
With HTML:
<body onkeypress="if(event.key==='Enter' && event.target.form){focusNextElement(event); return false;}">
With jQuery:
$(window).on('keypress', function (ev)
{
if (ev.key === "Enter" && ev.currentTarget.form) focusNextElement(ev)
}
And with Vanilla JS:
document.addEventListener('keypress', function (ev) {
if (ev.key === "Enter" && ev.currentTarget.form) focusNextElement(ev);
});
You can take focusNextElement() function from here:
https://stackoverflow.com/a/35173443/3356679

Easiest way to solve this problem with the focus function of JavaScript as follows:
You can copy and try it # home!
<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8">
<title></title>
</head>
<body>
<input id="input1" type="text" onkeypress="pressEnter()" />
<input id="input2" type="text" onkeypress="pressEnter2()" />
<input id="input3" type="text"/>
<script type="text/javascript">
function pressEnter() {
// Key Code for ENTER = 13
if ((event.keyCode == 13)) {
document.getElementById("input2").focus({preventScroll:false});
}
}
function pressEnter2() {
if ((event.keyCode == 13)) {
document.getElementById("input3").focus({preventScroll:false});
}
}
</script>
</body>
</html>

I had a problem to use enter key instead of Tab in React js .The solution of anjana-silva is working fine and just some small issue for input date and autocomplete as I am using MUI . So I change it a bit and add arrow keys (left/right) as well .
install jquery using npm
npm install jquery --save
write the below in App.js If you want to have this behavior In the whole of your application
import $ from 'jquery';
useEffect(() => {
$('body').on('keydown', 'input, select,button', function (e) {
if (e.keyCode === 13 || e.keyCode === 39) {
var self = $(this), form = self.parents('form:eq(0)'), focusable, next;
focusable = form.find('input,a,select,button,textarea').filter(':visible:not([readonly]):enabled');
next = focusable.eq(focusable.index(this) + 1);
if (next.length) {
next.focus();
}
return false;
}
if (e.keyCode === 37) {
var self = $(this), form = self.parents('form:eq(0)'), focusable, prev;
focusable = form.find('input,a,select,button,textarea').filter(':visible:not([readonly]):enabled');
prev = focusable.eq(focusable.index(this) - 1);
if (prev.length) {
prev.focus();
}
return false;
}
});
}, []);

I had a simular need.
Here is what I did:
<script type="text/javascript" language="javascript">
function convertEnterToTab() {
if(event.keyCode==13) {
event.keyCode = 9;
}
}
document.onkeydown = convertEnterToTab;
</script>

In all that cases, only works in Chrome and IE, I added the following code to solve that:
var key = (window.event) ? e.keyCode : e.which;
and I tested the key value on if keycode equals 13
$('body').on('keydown', 'input, select, textarea', function (e) {
var self = $(this)
, form = self.parents('form:eq(0)')
, focusable
, next
;
var key = (window.event) ? e.keyCode : e.which;
if (key == 13) {
focusable = form.find('input,a,select,button,textarea').filter(':visible');
next = focusable.eq(focusable.index(this) + 1);
if (next.length) {
next.focus();
} else {
focusable.click();
}
return false;
}
});

$("#form input , select , textarea").keypress(function(e){
if(e.keyCode == 13){
var enter_position = $(this).index();
$("#form input , select , textarea").eq(enter_position+1).focus();
}
});

You could programatically iterate the form elements adding the onkeydown handler as you go. This way you can reuse the code.