Numbers are concatenating instead of adding

[Choeeey]

this.score=this.game.time.totalElapsedSeconds().toFixed(0);

 this.score = this.score+5;

 

say the first this.score = 5.

I want the next this.score to equal 10.

 

But instead, I get 55.

 

I looked up the API, and it says this.score should be a number so I cannot understand why this is happening?

[Anderberg]

toFixed will return a string, that is why you get contatenation instead of addition. (source: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/toFixed)

You want to use Math.floor(this.game.time.totalElapsedSeconds()) instead.

[Choeeey]

Whoops! Thank you

[totallybueno]

And you can also check http://www.w3schools.com/jsref/jsref_parseint.asp

[ikkuh]

Math.floor( ... );

Notice that 'toFixed' rounds numbers instead of flooring them. As described in your link:

  "... The number is rounded if necessary, ..."

 

Of course 'Math.floor' might be exactly what Choeeey wants, but 'Math.round' gives the correct behavior of 'toFixed'.

[mwatt]

There are a number of different tricks you can use to force addition instead of concatenation.

 

Math.floor is one.  When I was "growing up" with JavaScript (heh, loooong time ago), I used to do things like subtracting a minus or multiplying * -1.  Hahah, cheesey, but it works.  Another thing that is useful when concatenating several strings on a line but two of the strings are meant to be added together is to parenthesize the two strings being added.

 

There are some bit shifting tricks too I think... but in any event, the overall most performant and most standard solution is parseInt (or parseFloat if necessary).  In specific cases, things like Math.floor or Math.round are more natural.

[tips4design]

Easier:

this.score = this.game.time.totalElapsedSeconds() | 0;

This does a btiwise or between the float number and 0, which converts the number to an integer. This is usually the correct way to solve your problem.

This also is the fastest way do do it (performance wise).