Constructor not working?

Question

New to JS and i'm having trouble figuring out how to run the constructor of newly created objects.

var player = new Player();
alert(player.getPosition()); // [ undefined, undefined ]

function Player()
{
    //afaik the x & y vars should fill when creating a new Player object.
    var x = Math.floor((Math.random() * 800) + 1), 
        y = Math.floor((Math.random() * 800) + 1);
}

Player.prototype.getPosition = function()
{
    return [this.x, this.y];
}

Your code does throw an `Unhandled Error: 'player.getPosition' is not a function`. See [Using prototype and dealing with execution order](http://stackoverflow.com/q/15184446/1048572) — Bergi, Aug 04 '14 at 16:21
@SLaks: I see now, but it's an issue that the *posted* code definitely has :-) — Bergi, Aug 04 '14 at 16:24
For the other issue, see [Javascript: Do I need to put this.var for every variable in an object?](http://stackoverflow.com/q/13418669/1048572) — Bergi, Aug 04 '14 at 16:25

score 2 · Accepted Answer · answered Aug 04 '14 at 16:21

2

The problem is you're not assigning x and y to the instance of Player. Try this instead

function Player()
{
    this.x = Math.floor((Math.random() * 800) + 1);
    this.y = Math.floor((Math.random() * 800) + 1);
}

answered Aug 04 '14 at 16:21

Mike Cluck

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score 0 · Answer 2 · answered Aug 04 '14 at 16:21

0

try this:

  function Player()
  {
//afaik the x & y vars should fill when creating a new Player object.
 this.x = Math.floor((Math.random() * 800) + 1); 
 this.y = Math.floor((Math.random() * 800) + 1);
   }

answered Aug 04 '14 at 16:21

Super Hornet

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Constructor not working?

2 Answers2