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Not allow Korean character(Hangul) for input text

I want to allow typing Latin Characters but I don't want user can type Korean Hangul characters.
Please help me answer. Thank you in advance.

Based on this article,
https://en.wikipedia.org/wiki/Korean_language_and_computers
You would want to do something like this (untested):
$(document).on('keypress', 'input', function (e) {
var key = event.which || event.keyCode;
// Hangul Syllables
if (key >= 0xAC00 && key <= 0xD7A3) {
e.preventDefault();
}
// Hangul Jamo
if (key >= 0x1100 && key <= 0x11FF) {
e.preventDefault();
}
// Hangul Compatibility Jamo
if (key >= 0x3130 && key <= 0x318F) {
e.preventDefault();
}
// Hangul Jamo Extended-A
if (key >= 0xA960 && key <= 0xA97F) {
e.preventDefault();
}
// Hangul Jamo Extended-B
if (key >= 0xD7B0 && key <= 0xD7FF) {
e.preventDefault();
}
});
However, this would not stop anyone from copying/pasting Hangul characters into the input field, you would need to find something separate for that.
A more simplified way is to use form validation (this is a more simplified approach):
<input type="text" pattern="[^가-힣]+">
What you should do is instead be testing for the characters on the server side and returning a form error.

Don't allow to reach higher than 9999 on an input? [duplicate]

This question already has answers here:
How to limit typing number in text input
(4 answers)
Closed 4 years ago.
$(document).on('keyup keydown',function(key){
if(key.which >= 48 && key.which <= 57 && $('#sell').val() >= 9999 ) {
return false;
}
else {
if(key.which >= 48 && key.which <= 57 && $('#sell').val() <= 9999 ) {
return true;
}
}
});
Basically what I want to do is prevent someone from reaching higher than 9999 on an input.
But the problem is that if they type "55555" it would go through.
They couldn't type any higher than that and could delete it, but I don't want them to get higher than 9999.
Does anyone have a solution?
EDIT:
I need to somehow also prevent the input from working if it detects a higher number.

Try this:
var lastVal;
$("#sell").on('keydown', function(e){
if(e.which === 8){ // allow backspace
return;
} else if((e.which < 48 || e.which > 57) && (e.which < 96 || e.which > 105) ) { //only allow numbers & num pad numbers
return false;
}
if(e.target.value <= 9999) lastVal = e.target.value; //prevent key holding
});
$("#sell").on('keyup', function(e){
if(e.target.value > 9999){
e.target.value = lastVal;
return false;
}
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" id=sell />

You could try something like this:
let sell = $('#sell');
let lastVal = 0;
sell.on('keyup keydown', function(key) {
let cc = key.which;
return (cc <= 57 && cc !== 32);
});
sell.on('input', function(evt) {
const newVal = sell.val();
if (newVal < 0 || newVal > 9999) {
sell.val(lastVal);
}
else {
lastVal = newVal;
}
});
Note that this only captures key events on the input itself, not the whole document. While this limits the user to typing digits (character below 48 (except space) are allowed because those are things like arrow keys and backspace), more work would be needed if you wanted to allow the user to perform actions like copy and paste.
The reason for not testing the val() of the input in the key event handler is a matter of timing: The key down event doesn't change the value of the input field, and the key up event comes after the value has been updated and it's too late to prevent the value change.
What this code does instead is let the value momentarily go out of range, but immediately reset it to the last valid value when that happens.
Plunker here: http://plnkr.co/edit/xsVQG1EzsDLMt8POCJUX?p=preview

Make the max length equal to 4 in HTML and use JS to force integer type, put max on input to prevent higher than 9999... Or do it manually for all of it . Up to you
With JS... on keydown: Strip non integers
if($("#inputID").val().length > 4){ KILL EXTRA LETTERS }
Once done.
If ($("#inputID").val() > 9999){ $("#inputID").val(9999); }
Remember, if this is for a form to validate the answer on the server side so the client can't override HTML and JS checks.

What jQuery event handler can be triggered after the deletion of all text in a form field?

If all of the text in a form field is selected and then the Backspace or Delete key are used, I want to be able to run some additional code. I have tried using change, blur, keypress, keydown. None seem to work.
Example that doesn't work:
$('input[id^=txtDate_]').on('keydown', function() {
enableSaveChanges();
});

Here is one way - http://jsfiddle.net/jayblanchard/6Uq85/
$('textarea[name="foo"]').keyup(function(e) {
var currentText = $(this).val();
if( 0 == currentText.length && (e.keyCode = 46 || e.keyCode == 8)) {
console.log('empty');
}
});
I should add that I am a fan of keyup() here as the event order for keypress,keydown and keyup are different. You can test to see which makes more sense for you. The reason that I use keyup here is because the textarea (or input) isn't actually empty when you press the key.

Use the key codes for 'delete' and 'backspace'
delete = 46
backspace = 8
example:
HTML:
<input type="text" id="input">
jQuery:
jQuery('#input').keyup(function(e) {
var str = jQuery('#input').val();
if( (e.keyCode == 46 || e.keyCode == 8) && str == "" ) {
alert("Hey");
}
});
EDITED: check for empty input field

Try this way for
<input type="txt" id="txt"/>
$('#test').keyup(function(e){
if($('#test').val() == '' && e.keyCode == 46 || e.keyCode == 8)){
console.log('Input is emptied');
}
});

Which is the proper way of filtering numeric values for a text field?

I'm working on a textfield working with the kind of validation that wouldn't let you enter other than numeric values. As so, my initial code looked quite simple and similar to this:
$(textField).onKeyPress(function(e) {
if (e.which < 48 && e.which > 57)
e.preventDefault();
});
This is fairly strightforward, but turns that (in the latest version of all browsers) Firefox will make this also prevent movement with the arrow keys and delete/backspace keys, whereas the other browsers would not.
Looking around I found that I would need to also check for these keys, and check for different properties exposed in the e event reference.
My final code looks something like this:
$(textField).onKeyPress(function(e) {
var code = e.which || e.keyCode;
if (code > 31 // is not a control key
&& (code < 37 || code > 40) // is not an arrow key
&& (code < 48 || code > 57) // is not numeric
&& (code != 46) // is not the delete key
)
e.preventDefault();
});
However, this feels to be too much to solve a fairly simple problem as just preventing non-numeric.
What am I doing wrong? Which is the best practice in terms of this kind of validation?

We'll respond to both keypresses, and the blur event. When somebody press a key, we check to see if the key entered is a number. If it is, we permit it. Otherwise, we prevent it.
If the field is blurred, we remove any non-numerical values, and all those values that follow. This will prevent the user from pasting in non-numerical strings:
$("#textfield").on("keypress blur", function(e){
if ( e.type === "keypress" )
return !!String.fromCharCode(e.which).match(/^\d$/);
this.value = this.value.replace(/[^\d].+/, "");
});
Demo: http://jsfiddle.net/jonathansampson/S7VhV/5/

Working demo http://jsfiddle.net/Pb2eR/23/ Updated Copy/Paste demo: http://jsfiddle.net/Pb2eR/47/ (In this demo wit you copy paste string with characters it won't allow else it will allow number to be copy pasted: tested in safari)
Demo for arrow key to work http://jsfiddle.net/gpAUf/
This will help you.
Note: in this version even if you copy paste it will set it to empty input box, tested in safari lion osx :)
Good Link: [1] How to allow only numeric (0-9) in HTML inputbox using jQuery?
code
$(".hulk").keyup(function(){
this.value = this.value.replace(/[^0-9\.]/g,'');
});
​
html
<input type="text" class="hulk" value="" />
​
Update for copy paste stuff
$(".hulk").keyup(function(){
this.value = this.value.replace(/[^0-9\.]/g,'');
});
$(".hulk").bind('input propertychange', function() {
this.value = this.value.replace(/[^0-9\.]/g,'');
});​
code from another demo
$(".hulk").bind('input propertychange', function(event) {
if( !(event.keyCode == 8 // backspace
|| event.keyCode == 46 // delete
|| (event.keyCode >= 35 && event.keyCode <= 40) // arrow keys/home/end
|| (event.keyCode >= 48 && event.keyCode <= 57) // numbers on keyboard
|| (event.keyCode >= 96 && event.keyCode <= 105)) // number on keypad
) {
event.preventDefault(); // Prevent character input
}
this.value = this.value.replace(/[^0-9\.]/g,'');
});
​

this will allow both int.
it also removes text if user copy and paste with mouse.
$(document).ready(function () {
$('#textfield').bind('keyup blur', function (e) {
if (e.type == 'keyup') {
if (parseInt($(this).val()) != $(this).val()) {
$(this).val($(this).val().slice(0, $(this).val().length - 1));
}
} else if (e.type == 'blur') {
$(this).val('');
}
});
});

Cancel the keydown in HTML

How can I cancel the keydown of a specific key on the keyboard, for example(space, enter and arrows) in an HTML page.

If you're only interested in the example keys you mentioned, the keydown event will do, except for older, pre-Blink versions of Opera (up to and including version 12, at least) where you'll need to cancel the keypress event. It's much easier to reliably identify non-printable keys in the keydown event than the keypress event, so the following uses a variable to set in the keydown handler to tell the keypress handler whether or not to suppress the default behaviour.
Example code using addEventListener and ignoring ancient version of Opera
document.addEventListener("keydown", function(evt) {
// These days, you might want to use evt.key instead of keyCode
if (/^(13|32|37|38|39|40)$/.test("" + evt.keyCode)) {
evt.preventDefault();
}
}, false);
Original example code from 2010
var cancelKeypress = false;
document.onkeydown = function(evt) {
evt = evt || window.event;
cancelKeypress = /^(13|32|37|38|39|40)$/.test("" + evt.keyCode);
if (cancelKeypress) {
return false;
}
};
/* For pre-Blink Opera */
document.onkeypress = function(evt) {
if (cancelKeypress) {
return false;
}
};

Catch the keydown event and return false. It should be in the lines of:
<script>
document.onkeydown = function(e){
var n = (window.Event) ? e.which : e.keyCode;
if(n==38 || n==40) return false;
}
</script>
(seen here)
The keycodes are defined here
edit: update my answer to work in IE

This is certainly very old thread.
In order to do the magic with IE10 and FireFox 29.0.1 you definitely must do this inside of keypress (not keydown) event listener function:
if (e.preventDefault) e.preventDefault();

jQuery has a nice KeyPress function which allows you to detect a key press, then it should be just a case of detecting the keyvalue and performing an if for the ones you want to ignore.
edit:
for example:
$('#target').keypress(function(event) {
if (event.keyCode == '13') {
return false; // or event.preventDefault();
}
});

Just return false. Beware that on Opera this doesn't work. You might want to use onkeyup instead and check the last entered character and deal with it.
Or better of use JQuery KeyPress

I only develop for IE because my works requires it, so there is my code for numeric field, not a beauty but works just fine
$(document).ready(function () {
$("input[class='numeric-field']").keydown(function (e) {
if (e.shiftKey == 1) {
return false
}
var code = e.which;
var key;
key = String.fromCharCode(code);
//Keyboard numbers
if (code >= 48 && code <= 57) {
return key;
} //Keypad numbers
else if (code >= 96 && code <= 105) {
return key
} //Negative sign
else if (code == 189 || code == 109) {
var inputID = this.id;
var position = document.getElementById(inputID).selectionStart
if (position == 0) {
return key
}
else {
e.preventDefault()
}
}// Decimal point
else if (code == 110 || code == 190) {
var inputID = this.id;
var position = document.getElementById(inputID).selectionStart
if (position == 0) {
e.preventDefault()
}
else {
return key;
}
}// 37 (Left Arrow), 39 (Right Arrow), 8 (Backspace) , 46 (Delete), 36 (Home), 35 (End)
else if (code == 37 || code == 39 || code == 8 || code == 46 || code == 35 || code == 36) {
return key
}
else {
e.preventDefault()
}
});
});