Converting string to number in javascript/jQuery

It sounds like this in your code is not referring to your .btn element. Try referencing it explicitly with a selector:

var votevalue = parseInt($(".btn").data('votevalue'), 10);

Also, don't forget the radix.

You can use parseInt(string, radix) to convert string value to integer like this code below

var votevalue = parseInt($('button').data('votevalue'));

DEMO

Although this is an old post, I thought that a simple function can make the code more readable and keeps with jQuery chaining code-style:

String.prototype.toNum = function(){
    return parseInt(this, 10);
}

can be used with jQuery:

var padding_top = $('#some_div').css('padding-top'); //string: "10px"
var padding_top = $('#some_div').css('padding-top').toNum(); //number: 10`

or with any String object:

"123".toNum(); //123 (number)`

Related