Sum of two input value by jquery

Question

I have code :

function compute() {
    if ($(\'input[name=type]:checked\').val() != undefined) {
        var a = $(\'input[name=service_price]\').val();
             


        

Answer 1

Cast them to a Number

$('#total_price').val(Number(a)+Number(b));

But before you do that

if (!isNaN($('input[name=service_price]').val()) {...

Answer 2

<script>
$(document).ready(function(){
var a =parseInt($("#a").val());
var b =parseInt($("#b").val());
$("#submit").on("click",function(){
var sum = a + b;
alert(sum);
});
});
</script>

Answer 3

use parseInt

   var total = parseInt(a) + parseInt(b);


    $('#total_price').val(total);

Answer 4

if in multiple class you want to change additional operation in perticular class that show in below example

$('.like').click(function(){    
var like= $(this).text();
$(this).text(+like + +1);
});

Answer 5

Because at least one value is a string the + operator is being interpreted as a string concatenation operator. The simplest fix for this is to indicate that you intend for the values to be interpreted as numbers.

var total = +a + +b;

and

$('#total_price').val(+a + +b);

Or, better, just pull them out as numbers to begin with:

var a = +$('input[name=service_price]').val();
var b = +$('input[name=modem_price]').val();
var total = a+b;
$('#total_price').val(a+b);

See Mozilla's Unary + documentation.

Note that this is only a good idea if you know the value is going to be a number anyway. If this is user input you must be more careful and probably want to use parseInt and other validation as other answers suggest.

Answer 6

use parseInt as a = parseInt($('input[name=service_price]').val())