Pushing to an objects array | JS

[Aprime]

I've got this object, which I use to create dynamic variables:

$("polyline").each(function (index) {
        polylineObj["allPoints"+index] = document.getElementsByTagName("polyline")[index].getAttribute("points");
        polylineObj["allPointsArray"+index] = polylineObj["allPoints"+index].split(" ");
});

But also in this function each, I have this

polylineObj["yAxis"+index] = [];
polylineObj["allPointsArray"+index].forEach(function (value, index) {
      if (index % 2) {
          polylineObj["yAxis"+index].push(value);
     }
});

The polylineObj["yAxis"+index] works, but when I try to push the value - it doesn't work...

Not sure why. Any idea?

[Aprime]

Fixed

Changed it to

$("polyline").each(function (num) {

So that it didn't interfere with the forEach that used the index

Anything you think I can improve on? Let me know.

Also, I use pure js instead of jQuery when getting all the polyline's so that it acknowledges them in an array.

[sharpnova]

I'm honestly still using pure jvs for everything. I've used jquery and I should probably use it more but I have always loved jvs so much.

That said, I think your problem is probably something to do with:

polylineObj["yAxis"+index].push(value);

You're pushing onto an element, not the array here. Push is only for adding elements to the end of an array. So it'd need to be polyineObj.push(value);

Unless there is some tricky advanced method for pushing to midpoints of an array. But I've never seen that.

[Diki]

At 2/19/18 08:32 PM, sharpnova wrote: That said, I think your problem is probably something to do with:

polylineObj["yAxis"+index].push(value);

You're pushing onto an element, not the array here. Push is only for adding elements to the end of an array. So it'd need to be polyineObj.push(value);

Here's making the element an array a couple lines before that:

polylineObj["yAxis"+index] = [];

The problem was he was using index as a variable name for these two loops:

$("polyline").each(function (index) {});

polylineObj["allPointsArray"+index].forEach(function (value, index) {});

The latter of which, so far as I can tell, was nested in the former's callback and overwriting his expected index value.

At 2/19/18 08:32 PM, sharpnova wrote: Unless there is some tricky advanced method for pushing to midpoints of an array. But I've never seen that.

The splice() function can do that:

var foo = ["foo", "bar", "baz"];

foo.splice(2, 0, "hello");
console.log(foo); // ["foo", "bar", "hello", "baz"]

[sharpnova]

At 2/20/18 09:48 AM, Diki wrote: Here's making the element an array a couple lines before that:

Ahh I see nm then.

The problem was he was using index as a variable name for these two loops:

Yep that must be it