An object or a number?

JavaScript
1

Hello I just have a syntax question,
I have this test app
adding gold every 2 seconds.
And when app start it retrieves gold on server like so.
this.gold = this.gold3+this.rubix.gold,
but problem is instead of adding numbers the code decide to
add them like 2+2=22
and after a while its upin several 1000.
both are objects by the way cause server value must be saved like an object
is there any way to fix this?

2

Assuming you got it from a server, it’s probably a String. You have to convert it to a number first. Try parseInt (or parseFloat if the number can have decimal places).

1 Like
3

As @n-kartha says, it’s because you’re using + with strings, so you are joining strings rather than adding numbers.

> 2  + 1
3
> 2 + '1'
'21'
> '2' + 1
'21'
> '2' + '1'
'21'

parseInt is useful, but verbose and there are caveats to using it:

> parseInt('2') + parseInt('1')
3
> parseInt('2') + parseInt('0xf')
17

The caveat is that you need to provide a radix, otherwise you may get strange results (eg JS may assume the number is not base-10)

> parseInt('2', 10) + parseInt('1', 10)
3
> parseInt('2', 10) + parseInt('0xf', 10)
NaN

So if the values you have saved are definitely going to be (base-10) numbers, you can use the Number function:

> Number('2') + Number('1')
3

Or you can use the unary plus operator to do the same thing:

> +'1'
1
> +'2'
2
> +'1' + +'2'
3
> var foo = '10'
> var bar = '20'
> +foo + +bar
30
1 Like
4

Did not know that the unary + did that :open_mouth:. Thanks for showing it to me! :smiley:

5

thanks I think this fix works. one of the data was a string so i try parse int it
i will see if this works )