Develop Reference

jQuery prevent writing letters and change comma to dot

I have tried to modify this code but it just wont work...probably some small mistake but i can't debug it :(
// replace , with . and block writing letters
$(document).on("keydown", ".amount", function () {
$(this).keydown(function(e) {
if(e.keyCode==188 || e.keyCode==110 || e.keyCode==108){
e.preventDefault();
$(this).val($(this).val() + '.');
}
var key = e.charCode || e.keyCode || 0;
return (key == 8 || key == 9 || key == 46 || key == 110 || key == 188 || key == 190 || (key >= 35 && key <= 40) || (key >= 48 && key <= 57) || (key >= 96 && key <= 105));
});
};
This is original code and it doesn't work on dynamic content
that is why i want to modify it!

How about just calling your ForceNumericOnly method when the user clicks into an input with .amount?
$(document).on('focus', '.amount', function(){
$(this).ForceNumericOnly();
});
https://jsfiddle.net/daveSalomon/r5n8xuhx/5/
You could (should) optimise it so it doesn't add the keydown handler again if it's already run the ForceNumericOnly code... something like:
$.fn.ForceNumericOnly = function() {
return this.each(function() {
if($(this).data('forceNumberOnly'){ return; }
$(this).data('forceNumberOnly',true);
...
});
};
https://jsfiddle.net/daveSalomon/r5n8xuhx/6/

There's no JS required - just use a number input:
<input class="amount" type="number">

Need to replace "comma" with 'dot'

Please help me to adjust an existing script to replace COMMA with DOT.
I use a script which limit the inserting character into Text fields. Only 1,2,3,4,5,6,7,8,9,0 and "." and "," are accepted to be inserted. I would like to have two buttons of inserting DOT - key==188 (comma) and key== 190 (dot).
jQuery.fn.ForceNumericOnly =
function()
{
return this.each(function()
{
$(this).keydown(function(e)
{
var key = e.charCode || e.keyCode || 0;
return (
key == 8 ||
key == 9 ||
key == 46 ||
key == 110 ||
key == 188 ||
key == 190 ||
(key >= 35 && key <= 40) ||
(key >= 48 && key <= 57) ||
(key >= 96 && key <= 105));
});
});
};
$("#iMONEY").ForceNumericOnly();
It can be tested HERE

Just use
if(e.keyCode == 188){
e.preventDefault();
$(this).val($(this).val() + '.');
}
Here you go. :)
For future references Mini-Tutorial.

The value of the textbox is updated after keypress event is fired. It's not a place to replace comma with dot. Use keyup event instead:
jQuery.fn.ForceNumericOnly =
function()
{
this.keyup(function(e)
{
// console.log("Change");
$(this).val($(this).val().replace(/,/g,"."));
});
};
$("#iMONEY").ForceNumericOnly();
DEMO

var key = e.charCode || e.keyCode || 0;
// 110 is numpad comma code
if (key === 188 && key === 110) {
e.preventDefault();
$(this).val($(this).val() + '.');
}

You need to use the Replace method
var someVariable = "1,2,3,4,5,6,7,8,9,0";
$mylabel.text( someVariable.replace(',', '.') );
EDIT:
If you are checking from TextBox then do it like this:
if(Key == 188){
var someVariable = $("#TEXTBOXID").val();
somVariable = someVariable.replace(',', '.');
}

How to allow only defined characters as input using jQuery?

How do i allow special characters such as hyphen,comma,slash,space key,backspace key,delete key along with alphanumeric values and restrict the rest in jQuery?
As this criteria(allowed characters/input values) varies from field to field, i would like to make it as a utility method which accepts input field id and allowed characters as parameters.
for example: limitCharacters(textid, pattern)

​You can just check the keyCode on keydown and run preventDefault() if match:
$('input').keydown(function(e) {
if (e.which == 8) { // 8 is backspace
e.preventDefault();
}
});​
http://jsfiddle.net/GVb6L/
If you need to restrict to certain chars AND keyCodes + make it into a jQuery plugin, try something like:
$.fn.restrict = function( chars ) {
return this.keydown(function(e) {
var found = false, i = -1;
while(chars[++i] && !found) {
found = chars[i] == String.fromCharCode(e.which).toLowerCase() ||
chars[i] == e.which;
}
found || e.preventDefault();
});
};
$('input').restrict(['a',8,'b']);​
http://jsfiddle.net/DHCUg/

I did something like this but in jQuery plugin format. This example will only allow numbers and full stops.
You can call this by writing:
$("input").forceNumeric();
And the plugin:
jQuery.fn.forceNumeric = function () {
return this.each(function () {
$(this).keydown(function (e) {
var key = e.which || e.keyCode;
if (!e.shiftKey && !e.altKey && !e.ctrlKey &&
// numbers
key >= 48 && key <= 57 ||
// Numeric keypad
key >= 96 && key <= 105 ||
// comma, period and minus, . on keypad
key == 190 || key == 188 || key == 109 || key == 110 ||
// Backspace and Tab and Enter
key == 8 || key == 9 || key == 13 ||
// Home and End
key == 35 || key == 36 ||
// left and right arrows
key == 37 || key == 39 ||
// Del and Ins
key == 46 || key == 45)
return true;
return false;
});
});
}

I would suggest using David solution for modifier keys like backspace and delete and this code below for characters:
var chars = /[,\/\w]/i; // all valid characters
$('input').keyup(function(e) {
var value = this.value;
var char = value[value.length-1];
if (!chars.test(char)) {
$(this).val(value.substring(0, value.length-1));
}
});
Also, I've experienced some problems with keydown so I'd do it on keyup.
Demo: http://jsfiddle.net/elclanrs/QjVGV/ (try typing a dot . or semicolon ;)

jquery - Numeric Only Text Field

I found this very short clean code to only allow numeric chars in a text field. Currently it only covers numbers 0-9 and backspace and delete. I wanted it to also include decimal/period, so I have been fighting with this to simply include keycode 110 and/or 190. I can not get it to work. Can anyone see what I am doing wrong?
$(document).ready(function() {
$('input.numberinput').bind('keypress', function(e) {
return ( e.which!=8 && e.which!=0 && (e.which<48 || e.which>57) ) || (e.which!=110) ? false : true ;
});
});
jsfiddle here: http://jsfiddle.net/justmelat/EN8pT/
html
<div class="label">Enter a number:</div>
<input type="text" name="txtNumber1" id="txtNumber1" value="" class="numberinput" />
<div class="label">Enter a number:</div>
<input type="text" name="txtNumber2" id="txtNumber2" value="" class="numberinput" />
</div>

Try:
$(document).ready(function () {
$('input.numberinput').bind('keypress', function (e) {
return !(e.which != 8 && e.which != 0 &&
(e.which < 48 || e.which > 57) && e.which != 46);
});
});​
JsFiddle: http://jsfiddle.net/EN8pT/1/

With the above answer you can still do 0.23.12.33 which is not a valid number.
http://www.texotela.co.uk/code/jquery/numeric/ is a great little lightweight plugin that I have used a lot. It takes the pain out of the above.

$("#input").keydown(function(event) {
var theEvent = event || window.event;
var key = theEvent.keyCode || theEvent.which;
// Allow: backspace, delete, tab, escape, and enter
if ( key == 46 || key == 8 || key == 9 || key == 27 || key == 13 || key == 110 || key == 190 ||
// Allow: Ctrl+A
(key == 65 && theEvent.ctrlKey === true) ||
// Allow: home, end, left, right
(key >= 35 && key <= 39)) {
// let it happen, don't do anything
return;
}
else {
// Ensure that it is a number and stop the keypress
if (theEvent.shiftKey || (key < 48 || key > 57) && (key < 96 || key > 105 )) {
theEvent.preventDefault();
}
}
});
with keycode 110 and 190

using jQuery/javascript to restrict price field input

I found the following jQuery code on the internet, but I soon found that it had a deficiency in that it dit not accept a decimal point (ascii code 46) - even though the code appears to allow it.
Currently, I cannot enter prices like 1.23, since the the period is ignored and I get 123 instead.
Can anyone spot whty this is not working?
// Numeric only control handler
$.fn.ForceNumericOnly =
function()
{
return this.each(function()
{
$(this).keydown(function(e)
{
var key = e.charCode || e.keyCode || 0;
// allow backspace, tab, delete, arrows, numbers and keypad numbers ONLY
return (
key == 8 ||
key == 9 ||
key == 46 ||
(key >= 37 && key <= 40) ||
(key >= 48 && key <= 57) ||
(key >= 96 && key <= 105));
})
})
};
I am using the plugin like this:
$(function(){
$('#price_field').ForceNumericOnly();
});

The other users have pretty much answered your question already, but I wanted to provide you with this link.
http://unixpapa.com/js/key.html
I found it quite useful when dealing with keyboard events and making them cross-browser compatible.
I hope this helps.

Just add the . (code 190 and 110) to the checks:
// Numeric only control handler
$.fn.ForceNumericOnly =
function()
{
return this.each(function()
{
$(this).keydown(function(e)
{
var key = e.charCode || e.keyCode || 0;
// allow backspace, tab, delete, arrows, numbers and keypad numbers ONLY
return (
key == 8 ||
key == 9 ||
key == 46 ||
key == 190 || // normal .
key == 110 || // keypad .
(key >= 37 && key <= 40) ||
(key >= 48 && key <= 57) ||
(key >= 96 && key <= 105));
})
})
};

You should add the key code 190 to accept "."
// Numeric only control handler
$.fn.ForceNumericOnly = function() {
return this.each(function()
{
$(this).keydown(function(e)
{
var key = e.charCode || e.keyCode || 0;
// allow dot, backspace, tab, delete, arrows, numbers and keypad numbers ONLY
return (
key == 190 ||
key == 8 ||
key == 9 ||
key == 46 ||
(key >= 37 && key <= 40) ||
(key >= 48 && key <= 57) ||
(key >= 96 && key <= 105));
})
})
};

You need to include 190 and 110 for both decimal points.

// Numeric only control handler
$.fn.ForceNumericOnly =
function()
{
return this.each(function()
{
$(this).keydown(function(e)
{
var key = e.charCode || e.keyCode || 0;
// allow backspace, tab, delete, arrows, numbers and keypad numbers ONLY
return (
key == 190 || //add this line. 190 is the keycode for a period
key == 110 || //and this line. 110 is the keycode for a decimal
key == 8 ||
key == 9 ||
key == 46 ||
(key >= 37 && key <= 40) ||
(key >= 48 && key <= 57) ||
(key >= 96 && key <= 105));
})
})
};