Loop in an Array?

JavaScript
1

I would like to put all my coordinates into an array and have a loop display each one but with a Google function.

Here’s the code, which draws the points on google map:

 var flightPlanCoordinates = [
    new google.maps.LatLng(37.772323, -122.214897),
    new google.maps.LatLng(21.291982, -157.821856),
    new google.maps.LatLng(-18.142599, 178.431),
    new google.maps.LatLng(-27.46758, 153.027892)
  ];

I would like to be able to do something like this:

var arrPos = new Array([37.772323, -122.214897], [21.291982, -157.821856], [-18.142599, 178.431], etc. );

var flightPlanCoordinates = [ +
   for (i=0; i<arrPos.length; i++){
      new google.maps.LatLng(arrPos[0]) + ", "
   }
   + "];"

I know you can put a loop in an array but is there an alternate method to retrieving the points from the array??

tks

2

You can use the push method to add items to an array.

Note: I’ve changed arrPos to store the coords as object references, so that it’s easier to work with them.


var arrPos = [
    {lat: 37.772323, long: -122.214897},
    {lat: 21.291982, long: -157.821856},
    {lat: -18.142599, long: 178.431}
],
    flightPlanCoordinates = [];

for (i = 0; i < arrPos.length; i += 1) {
    flightPlanCoordinates.push(new google.maps.LatLng(arrPos[i].lat, arrPos[i].long));
}

Or if you want something more expressive, you can use the forEach method instead of the loop, but in cases such as what you’re doing here, a more preferred way is to combine forEach and push by using the [url=“https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Array/map”]map method which uses one array to create another array.


function createGoogleCoords(coords) {
    return new google.maps.LatLng(coords.lat, coords.long);
}

var arrPos = [
    {lat: 37.772323, long: -122.214897},
    {lat: 21.291982, long: -157.821856},
    {lat: -18.142599, long: 178.431}
],
    flightPlanCoordinates = arrPos.map(createGoogleCoords);