checking if number entered is a digit in jquery

Question

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 ente

Answer 1

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

Answer 2

$(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;
        }
    });
});

Answer 3

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
}

Answer 4

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