checking if number entered is a digit in jquery
JavascriptJqueryValidationJavascript Problem Overview
I have a simple textbox in which users enter number.
Does jQuery have a isDigit function that will allow me to show an alert box if users enter something other than digits?
The field can have decimal points as well.
Javascript Solutions
Solution 1 - Javascript
I would suggest using regexes:
var intRegex = /^\d+$/;
var floatRegex = /^((\d+(\.\d *)?)|((\d*\.)?\d+))$/;
var str = $('#myTextBox').val();
if(intRegex.test(str) || floatRegex.test(str)) {
alert('I am a number');
...
}
Or with a single regex as per @Platinum Azure's suggestion:
var numberRegex = /^[+-]?\d+(\.\d+)?([eE][+-]?\d+)?$/;
var str = $('#myTextBox').val();
if(numberRegex.test(str)) {
alert('I am a number');
...
}
Solution 2 - Javascript
Forget regular expressions. JavaScript has a builtin function for this: isNaN():
isNaN(123) // false
isNaN(-1.23) // false
isNaN(5-2) // false
isNaN(0) // false
isNaN("100") // false
isNaN("Hello") // true
isNaN("2005/12/12") // true
Just call it like so:
if (isNaN( $("#whatever").val() )) {
// It isn't a number
} else {
// It is a number
}
Solution 3 - Javascript
there is a simpler way of checking if a variable is an integer. you can use $.isNumeric() function. e.g.
$.isNumeric( 10 ); // true
this will return true but if you put a string in place of the 10, you will get false.
I hope this works for you.
Solution 4 - Javascript
Following script can be used to check whether value is valid integer or not.
function myFunction() {
var a = parseInt("10000000");
if (!isNaN(a) && a <= 2147483647 && a >= -2147483647){
alert("is integer");
} else {
alert("not integer");
}
}
Solution 5 - Javascript
Value validation wouldn't be a responsibility of jQuery. You can use pure JavaScript for this. Two ways that come to my mind are:
/^\d+$/.match(value)
Number(value) == value
Solution 6 - Javascript
With jQuery's validation plugin you could do something like this, assuming that the form is called form and the value to validate is called nrInput
$("form").validate({
errorElement: "div",
errorClass: "error-highlight",
onblur: true,
onsubmit: true,
focusInvalid: true,
rules:{
'nrInput': {
number: true,
required: true
}
});
This also handles decimal values.
Solution 7 - Javascript
String.prototype.isNumeric = function() {
var s = this.replace(',', '.').replace(/\s+/g, '');
return s == 0 || (s/s);
}
usage
'9.1'.isNumeric() -> 1
'0xabc'.isNumeric() -> 1
'10,1'.isNumeric() -> 1
'str'.isNumeric() -> NaN
Solution 8 - Javascript
var yourfield = $('fieldname').val();
if($.isNumeric(yourfield)) {
console.log('IM A NUMBER');
} else {
console.log('not a number');
}
JQUERY DOCS:
Solution 9 - Javascript
jQuery is a set of JavaScript functions, right? So you could use JavaScript's regular expression support to validate the string. You can put this in a jQuery callback if you like, too, since those just take anonymously-declared function bodies and the functions are still JavaScript.
Solution 10 - Javascript
$(document).ready(function () {
$("#cust_zip").keypress(function (e) {
//var z = document.createUserForm.cust_mobile1.value;
//alert(z);
if (e.which != 8 && e.which != 0 && (e.which < 48 || e.which > 57)) {
$("#errmsgzip").html("Digits Only.").show().fadeOut(3000);
return false;
}
});
});