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Tabs default action is not stopped event though i use e.preventDefault()

I am showing a text area in a modal when I pressed tab it moves to the next input I wrote code to stop this but I didn't work for me.(when I pressed tab the execution even not coming to the acceptTabsSpace function)
$(document).on("keyup", "#collection-text-input", acceptTabsSpace);
function acceptTabsSpace(e){
var keyCode = e.keyCode || e.which;
if (keyCode == 9) {
e.preventDefault();
return false;
}
}

Add the listener to trigger on keydown instead:
$(document).on("keydown", "#collection-text-input", acceptTabsSpace);
function acceptTabsSpace(e){
var keyCode = e.keyCode || e.which;
if (keyCode === 9) {
e.preventDefault();
return false;
}
}

Use keydown instead key up and for tabspaces press tab twice.
$(document).on("keydown", "#collection-text-input", acceptTabsSpace);
function acceptTabsSpace(e) {
var keyCode = e.keyCode || e.which;
if (e.keyCode === 9) {
e.preventDefault();
this.value = this.value.substring(0, this.selectionStart) + "\t" +
this.value.substring(this.selectionEnd);
this.selectionEnd = s + 1;
}
}

Is there a way in JavaScript to change Enter to Shift + Enter

This is what I tried and obviously failed:
ed.on('keyup', function(e){
console.log(e.keyCode)
if(e.keyCode == 13 && !e.shiftKey){
e.shiftKey = true;
e.keyCode = 13;
$(this).trigger(e);
}
else if (e.keyCode == 13 && e.shiftKey){
e.shiftKey = false;
e.keyCode = 13;
$(this).trigger(e);
}
});
Is there a way to do this cause based on what I seen I think I'm on the right track and most likely just not triggering it early or something similar.
Additionally, I tried using 'keypress' instead and had no luck with that.

document.onkeydown = function onkeydown(e) {
if (e.keyCode == 13 && e.shiftKey==false) {
e.preventDefault();
document.execCommand("insertLineBreak");
}
}

When enter is pressed without shift, trigger keydown with enter and shift!
$('input').on('keydown', function(event) {
if (event.keyCode == 13 && !event.shiftKey) {
$(this).trigger(jQuery.Event("keydown", {
keyCode: 13, // ENTER
shiftKey: true
}));
} else if (event.keyCode == 13 && event.shiftKey) {
console.log('shift + enter');
}
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input/>

Hotkey combinations don't work if done fast

I'm trying to make a hotkey for a web app, for example Ctrl + z performs the undo function.
It seems that when I press the keys fast (as I'm used to from using desktop apps a lot), it doesn't register. The single key press registers, but it misses the combination for some reason.
From what I understand, you have to keep track of which buttons are held down via keypress events, which is what I've done below.
Try the code below. Hitting Z outputs Z. Hitting CTRL then Z slowly outputs CTRL + Z. Hitting CTRL then Z quickly outputs Z. When I perform the action at the same speed in say Notepad for windows, it works flawlessly almost every time.
https://codepen.io/samkeddy/pen/YQjgdZ?editors=1010#0
var ctrlPressed=false, altPressed=false;
window.addEventListener("keydown", function (e) {
hotkey = e;
if (e.keyCode == 17) ctrlPressed = true;
if (e.keyCode == 18) altPressed = true;
e.preventDefault();
});
window.addEventListener("keyup", function (e) {
hotkey = window.event;
if (e.keyCode == 17) ctrlPressed = false;
if (e.keyCode == 18) altPressed = false;
if (e.keyCode == 90){
if (altPressed && ctrlPressed && e.keyCode == 90)
addText('ALT + CTRL + Z');
else if (ctrlPressed && e.keyCode == 90)
addText('CTRL + Z');
else
addText('Z');
}
});
//meaningless, just adds text to doc so you can see it
function addText(text) {
var theDiv = document.getElementById("output");
theDiv.appendChild(document.createElement("br"));
var content = document.createTextNode(text);
theDiv.appendChild(content);
}

Use e.ctrlKey to check if ctrl is down instead of variables, and just check for the hotkey combination on keydown, don't do anything on key up.
https://codepen.io/samkeddy/pen/gRdBpq
function KeyPress(e) {
var evtobj = window.event? event : e
if (evtobj.keyCode == 90 && evtobj.ctrlKey) addText("CTRL + Z");
else if (evtobj.keyCode == 90) addText("Z");
}
document.onkeydown = KeyPress;

Adding keypress Events that use an existing function

I have used a function which is activated on click events. I want to do the same using keypress events.
function addToText(target) {
var exp = target.target;
//alert(exp.value);
if (newExp) {
//clearText();
document.getElementById("expression").value = exp.value;
newExp=false;
}
else
document.getElementById("expression").value = document.getElementById("expression").value + exp.value;
}
This is the function used. How do I modify it to use for keypress events also. Currently, it does not work initially(for keypress events). But after clicking once, then any keypress returns the same number that was previously clicked.
Full code here:http://codepen.io/jpninanjohn/pen/JXVpYb?editors=1010

Here's is your final solution, I test if charcode is between 48 and 57, what it means, numbers between 0 and 9.
document.addEventListener('keypress', function(e){
if (e.which >= 48 && e.which <= 57)
document.getElementById("expression").value+= String.fromCharCode(e.which);
});

You can use this function-
window.onkeyup = function(e) {
var key = e.keyCode ? e.keyCode : e.which;
document.getElementById("expression").value += key-48; //for getting the number
alert(key);
if (key == 38) {
//whatever
}else if (key == 40) {
// whatever
}
}
source
And you need to add + to the =
document.getElementById("expression").value+=
instead of -
document.getElementById("expression").value=

You have to add a different function for keyPress event, because the keypress event get the value of pressed key differently, not target.target
function addToTextKeypress(event) {
var exp = String.fromCharCode(event.keyCode);
//alert(exp);
if (newExp) {
//clearText();
document.getElementById("expression").value = exp;
newExp=false;
}
else
document.getElementById("expression").value = document.getElementById("expression").value + exp;
}
Later you need to remove exp.value since it has the direct value

how to disable the function of ESC key in JavaScript?

In my chat application there are some text fields which gets the user login details.
when filling the user details,If user suddenly pressed the ESC key,the data will be lost.
I need to disable the function of ESC key ? which event I need to use ? how can I do that.
my Java Script code is ,
function esc(e){
e = e || window.event || {};
var charCode = e.charCode || e.keyCode || e.which;
if(charCode == 27){
return false;
}
}
Searched a lot in Stack overflow and google.Nothing worked.Please any one help me to do that . Thanks..

You can bind an eventlistener to your input field to catch the Event when Esc is pressed and supress it.
document.querySelector("input").addEventListener("keydown",function(e){
var charCode = e.charCode || e.keyCode || e.which;
if (charCode == 27){
alert("Escape is not allowed!");
return false;
}
});
Example

I got the solution to control the " F5 , Esc , BackSpace(BS) " keys with the following code.
My Java Script code will be ,
document.attachEvent("onkeydown", win_onkeydown_handler);
function win_onkeydown_handler() {
switch (event.keyCode) {
case 116 : // 'F5'
event.returnValue = false;
event.keyCode = 0;
break;
case 27: // 'Esc'
event.returnValue = false;
event.keyCode = 0;
break;
case 08: // 'BackSpace'
if (event.srcElement.tagName == "INPUT"
|| event.srcElement.tagName == "TEXTAREA") {
} else {
event.returnValue = false;
event.keyCode = 0;
}
break;
}
}
Thanks who are all supported me to do this and for your suggestions.

I have used this for a login popup code:
jQuery(document).keyup(function(e){
if(e.keyCode==27 && popupStatus==1){
// alert('not allowed !!!');
// or any other code
return false;
}
});

I have done something similar using jquery to limit entry to numbers
$(inputBox).keydown(function(event) {
// Allow only backspace and delete
var allowed_keys = [
46, // delete
8, // backspace
];
if ($.inArray(event.keyCode, allowed_keys) != -1) {
// let it happen, don't do anything
}
else {
// Ensure that it is a number and stop the keypress
if (event.keyCode < 48 || event.keyCode > 57 ) {
event.preventDefault();
}
}
});