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How to disAllow minus (-) in text box

Here I have a function which only allows numeric and percentage. But it is allowing minus(-), I want to restrict that minus in that script. How can I restrict.Here is my script.Or please suggest me a dirctive for this.
function validateQty(el, evt) {
var charCode = (evt.which) ? evt.which : event.keyCode
if (charCode != 45 && charCode != 8 && charCode != 37 && (charCode != 46) && (charCode < 48 || charCode > 57))
return false;
if (charCode == 46) {
if ((el.value) && (el.value.indexOf('.') >= 0))
return false;
else
return true;
}
return true;
var charCode = (evt.which) ? evt.which : event.keyCode;
var number = evt.value.split('.');
if (charCode != 46 && charCode > 31 && (charCode < 48 || charCode > 57)) {
return false;
}
};

You can allow what you want to be as input. Do something like this.
function restrictInput(el) {
el.addEventListener('input', function(e) {
if (!e.target.value.match(/^\d+$|%$/)) {
e.target.value = e.target.value.slice(0, -1)
}
console.log(e.target.value);
})
}
restrictInput(document.getElementById("input1"));
restrictInput(document.getElementById("input2"));
<input id="input1">
<input id="input2">
updated: As asked by OP. A generic function to handle inputs.
NOTE: You can add more restrictions as you want inside this function

You could use input=number
<input type="number" min="0" />
Using javascript you could do:
// Select your input element.
var numInput = document.querySelector('input');
// Listen for input event on numInput.
numInput.addEventListener('input', function () {
// Let's match only digits.
var num = this.value.match(/^\d+$/);
if (num === null) {
// If we have no match, value will be empty.
this.value = "";
}
}, false)
If the data from the input field will be sent to the server, make sure to add this validation on the server too.

I think you can simplify your script by just testing it against a regular expression.
So your function would essentially change to something like this
function validateQty(el, evt)
{
var regex = new RegExp(/^\d+$|%$/);
return regex.test(el.value);
};
JSFiddle

Javascript currency regular expression replace

For my business web application I want a user to only be able to enter valid currency values in a textbox.
Currently I use
$input.val($input.val().replace(/[^.\d]/g, ''));
But this doesn't take in consideration order or multiple decimal seperators.
So the user either has to enter a whole integer or a valid decimal value e.g.:
49
49.50
Bonus points if this is allowed too:
.50 (for 0.50)
So I don't want to validate, I want to restrict typing into the textbox. Is this possible with a single regexp replace?

We can do this in two steps. Restrict the user to type only the number characters and . character.
var charCode = (evt.which) ? evt.which : event.keyCode
if (charCode < 31 && (charCode > 48 || charCode < 57))
return true;
return false;
And the next one is for allowing the .:
var charCode = (evt.which) ? evt.which : event.keyCode
if (charCode == 46 && (charCode > 31 && (charCode < 48 || charCode > 57)))
return true;
return false;
The next step will be not allowing double periods.
var charCode = (evt.which) ? evt.which : event.keyCode
if (charCode == 46 && (charCode > 31 && (charCode < 48 || charCode > 57)))
if (charCode == 46 && value.indexOf(".") !== false)
return true;
return false;
Hope you can have this as a starting point.
Snippet
Open Deal: Break it if you can.
function check(inp) {
var charCode = (event.which) ? event.which : event.keyCode;
console.log(charCode);
if (charCode == 8)
return true;
if ((charCode > 46 && charCode < 58) || (charCode > 95 && charCode < 106) || charCode == 110 || charCode == 190)
if (charCode == 110 || charCode == 190)
if (inp.value.indexOf(".") == -1)
return true;
else
return false;
else
return true;
return false;
}
<input type="text" onkeydown="return check(this);" />

It's more user friendly to advise of errors and let users fix them themselves. You might consider using the keyup event, but showing an error too early (before the user has had a chance to enter a valid value) can be annoying too. e.g.
function validate(el) {
var type = el.className;
var errEl = document.getElementById(el.name + 'Err');
if (type == 'typeCurrency') {
var currencyRe = /^-?(\d+(\.\d{1,2})?|\.\d{1,2})$/;
errEl.style.visibility = currencyRe.test(el.value)? 'hidden' : 'visible';
}
}
.errorMessage {
color: red;
background-color: white;
visibility: hidden;
}
Cost <input onblur="validate(this)" name="foo" class="typeCurrency" placeholder="0.00"><br>
<span id="fooErr" class="errorMessage">Please enter a valid cost, e.g. 2.45</span>

allow only float number with backspace and left and right arrow

I want to allow only one . in textfield, with backspace, left and right arrow.
I found this this link.
only allow numbers, backspace, delet, left arrow and right arrow keys in textbox
I addded one more validation in above code, so that user can add only . in textfield, but it's not working.
JS
function validateQty(event) {
var key = window.event ? event.keyCode : event.which;
if (event.keyCode == 8 || event.keyCode == 46 || event.keyCode == 37 || event.keyCode == 39 ) {
if($(this).val().indexOf('.') == -1)
return true;
else
return false;
}
else if ( key < 48 || key > 57 ) {
return false;
}
else return true;
};
JSFiddle

The problem as I see it is that in the line if($(this).val().indexOf('.') == -1), the this is the Window object not the input control.
Try adding an ID to the input control and reference the same in the code as:
function validateQty(event) {
var key = window.event ? event.keyCode : event.which;
if (event.keyCode == 8 || event.keyCode == 46 || event.keyCode == 37 || event.keyCode == 39 ) {
if($('#IdofInputControl').val().indexOf('.') == -1)
return true;
else
return false;
}
else if ( key < 48 || key > 57 ) {
return false;
}
else return true;
};
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" ID="IdofInputControl" onkeypress='return validateQty(event);'>
And your validation should work!

function isNumber(evt) {
evt = (evt) ? evt : window.event;
var charCode = (evt.which) ? evt.which : evt.keyCode;
if (charCode > 31 && (charCode < 48 || charCode > 57)&&(evt.which != 46 || $('#refAmount').val().indexOf('.') != -1)) {
return false;
}
return true;
}

You can use following code with some modifications of keys which you want to use or not.
jQuery("#YourSelector").keypress(function (evt) {
var charCode = (evt.which) ? evt.which : evt.keyCode;
if (charCode != 46 && charCode > 31 && (charCode < 43 || charCode > 57)){
return false;
}else{
return true;
}
});

How to avoid entering special characters in JavaScript

On html I have one input box in which I just want to enter numeric values. I used following function:
function allowNumbersOnly(event,locale) {
if(locale=='en' && (event.keyCode==190 || event.keyCode==110)){
return true;
}
else if(locale=='nl' && (event.keyCode==188 || event.keyCode==190 || event.keyCode==110)){
return true;
}
if(event.keyCode==189 || (event.keyCode==109) ){
return true;
}
var key = event.charCode || event.keyCode || 0;
// allow backspace, tab, delete, arrows, numbers and keypad numbers ONLY
if (
key == 8 ||
key == 9 ||
key == 46 ||
(key >= 37 && key <= 40) ||
(key >= 48 && key <= 57) ||
(key >= 96 && key <= 105)){
}else{
event.preventDefault();
}
}
This code works fine. But when I am pressing shift key+ any number from keyboard then special character gets entered. Can anyone tell me how to solve this issue?

Try the following function
function isNumber(evt) {
evt = (evt) ? evt : window.event;
var charCode = (evt.which) ? evt.which : evt.keyCode;
if (charCode > 31 && (charCode < 48 || charCode > 57)) {
return false;
}
return true;
}
If you are using HTML5 just try
<input type="number">

Try like this:
function blockspecialcharacter(e) {
var key= document.all ? key= e.keyCode : key= e.which;
return ((key > 64 && key < 91) || (key> 96 && key< 123) || key== 8 || key== 32 || (key>= 48 && key<= 57));
}
Check demo here

shiftKey event attribute returns a Boolean value that indicates whether or not the "SHIFT" key was pressed
if (event.shiftKey==1)
{
alert("The shift key was pressed!")
}
else
{
alert("The shift key was NOT pressed!")
}
so you can exit from your function if shift is pressed using value of event.shiftKey
// in your code
function allowNumbersOnly(event,locale) {
if (event.shiftKey==1) {
return false;
} // RETURN if shift key got clicked.
if (locale=='en' && (event.keyCode==190 || event.keyCode==110)) {
return true;
}
else if (locale=='nl' && (event.keyCode == 188 ||
event.keyCode == 190 ||
event.keyCode == 110)) {
return true;
}
if (event.keyCode==189 || (event.keyCode==109)) {
return true;
}
var key = event.charCode || event.keyCode || 0;
// allow backspace, tab, delete, arrows, numbers and keypad numbers ONLY
if (key == 8 ||
key == 9 ||
key == 46 ||
(key >= 37 && key <= 40) ||
(key >= 48 && key <= 57) ||
(key >= 96 && key <= 105)) {
}
else {
event.preventDefault();
}
}

Try this:
function blockSpecialChars(e){
var e = e || window.event;
var k = e.which || e.keyCode;
var s = String.fromCharCode(k);
return !/^[\\\"\'\;\:\>\|~`!##\$%^&*\(\)]$/i.test(s);
}
Add or remove the special characters from the above code to make it as you need.

Enable dot and Tab in textboxes

I have text boxes which only allow to enter numeric values. I handled it using a JavaScript. But it doesn't allow me to enter dot and tab movement. I need those two as well. How to change this code to enter dot symbol and tab movement.
function CheckNumeric(e) {
if (window.event) // IE
{
if ((e.keyCode < 48 || e.keyCode > 57) & e.keyCode != 8) {
event.returnValue = false;
return false;
}
}
else // Fire Fox
{
if ((e.which < 48 || e.which > 57) & e.which != 8) {
e.preventDefault();
return false;
}
}

this code is tested and works..this may help u..!!
<script type="text/javascript">
function onlyDotsAndNumbers(txt, event) {
var charCode = (event.which) ? event.which : event.keyCode
if (charCode == 46) {
if (txt.value.indexOf(".") < 0)
return true;
else
return false;
}
if (charCode > 31 && (charCode < 48 || charCode > 57))
return false;
return true;
}
> <asp:TextBoxID="txt1"runat="server"onkeypress="return onlyDotsAndNumbers(this,event)"/>