CODEWITHSUNDEEP
javascript
CLiown
CLiown

Reputation: 13853

Javascript maths not working

Here is my Javascript:

var total = $(this).text();
var calc = total * 100;
var paid = calc * 0.333;

The HTML is simple: 

<div class="price"><span>£0.21</span></div>

How can I remove the '£' char from the string so I can do the maths?

Upvotes: 2

Views: 206

Answers (7)

oezi
oezi

Reputation: 51817

  1. use slice(), substr() or substring() to cut out the part you need
  2. use parseFloeat() or parseInt() before doing calculations with your number to be sure it is a number

Upvotes: 1

CarpeNoctumDC
CarpeNoctumDC

Reputation: 1760

parseint is wrong.. it would be parsefloat...

but you need to strip the first char before you parsefloat otherwise it will return NaN (not a number)

var total = "£0.21";
total = total.substring(1);
total = parseFloat(total);
var calc = total * 100; 
var paid = calc * 0.333; 
alert(paid);

Upvotes: 0

GolezTrol
GolezTrol

Reputation: 116180

Use SubStr to copy from the second character (#1). Use parseFloat to convert to float.

var total = $(this).text().substr(1).parseFloat();
var calc = total * 100;
var paid = calc * 0.333;

Upvotes: 0

spolu
spolu

Reputation: 660

If you always have a '£' sign at the beginning of your string, you can use a substring before assigning total (which will cast from string to number, correctly this time).

You can also rely on a regular expression such as

/[-+]?[0-9]*\.?[0-9]*/

Cheers,

-stan

Upvotes: 1

Skilldrick
Skilldrick

Reputation: 70879

You need to slice the string to remove the '£':

var total = $(this).text().slice(1);

Upvotes: 1

user113716
user113716

Reputation: 322592

This will remove all characters from the string that are not a number or decimal point.

var total = $(this).text().replace(/[^\d.]/g,'');
var calc = total * 100;
var paid = calc * 0.333;

Useful if there are any comma separators as well.

The * will take care of the conversion from String. If you want something more explicit, you can use the unary + operator.

var total = +($(this).text().replace(/[^\d.]/g,'')); // <-- has + at beginning
var calc = total * 100;
var paid = calc * 0.333;

Upvotes: 4

zzzzBov
zzzzBov

Reputation: 179256

check out the parseFloat function.

Edit: whoops, i meant to write parseFloat; couple bits of difference.

Upvotes: 0

Related Questions