printing value from Javascript Object

Question

is the first time that I use OOP in Javascript, called markerPlaces that have some data in it:

enter image description here

I want to access to the property lat for each node via for statement: I tried:

for(i=0;i<markerPlaces.length;i++){
    console.log(markerPlaces[i][lat]);
}

But it doesn't work. The error is "lat is undefined".

The complete function is:

function initialize(markerPlaces) {
    (function(window, google, maplib){
        var mapOptions = maplib.MAP_OPTIONS,
        domElement = document.getElementById('map'),
        //map declaration
        map = new google.maps.Map(domElement, mapOptions);
        console.log(markerPlaces);
        //for statement for markers
        for(i=0;i<markerPlaces.length;i++){
            console.log(markerPlaces[0].posts.lat);
        }
        markers = new google.maps.Marker({
                position: {
                    lat:45.0690246,
                    lng:7.6932346
                },
                map: map,
                icon: 'http://example.com/wp-content/themes/turisti/img/poi.png'
            })
    }(window, google, window.maplib || (window.maplib = {})));
}

but firebug result is:

enter image description here

It seems `markerPlaces` is a an array with a single element. I believe you actually have to iterate over `markerPlaces[0].posts`. — Felix Kling, Oct 23 '14 at 16:21
No. As I said, you have to **iterate** over `markerPlaces[0].posts`. I.e. `for (var i = 0; i < markerPlaces[0].posts.length; i++) { /* do something with markerPlaces[0].posts[i] */ }`. Or make it simpler by assigning `var posts = markerPlaces[0].posts;` first. If you are unfamiliar with arrays and objects, I recommend to read the MDN JavaScript Guide: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_Objects, https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Predefined_Core_Objects#Array_Object . FYI, this has nothing to do with OOP. — Felix Kling, Oct 23 '14 at 16:55

Matt · Answer 1 · 2014-10-23T16:17:26.643

1

You can access it via:

for (var i = 0; i < markerPlaces.length; i++)
{
    console.log(markerPlaces[i].lat);
    // or
    console.log(markerPlaces[i]["lat"]);
}

Make sure you put the var keyword before i = 0 in your for loop as well.

edited Oct 23 '14 at 16:17

answered Oct 23 '14 at 15:36

Matt

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if i try this but the result is undefined – ghost Oct 23 '14 at 15:40
You need to be using it inside the loop you created in your example. I'll edit that bit in just for clarity. – Matt Oct 23 '14 at 15:46
the result is undefined, it'll be usefull if i post the complete function? – ghost Oct 23 '14 at 16:01
Very much so. The more relevant code provided, the easier it is to find a solution. – Matt Oct 23 '14 at 16:03
You seem to be missing a `var` keyword in your for loop declaration. – Matt Oct 23 '14 at 16:18
it doesn't change anything – ghost Oct 23 '14 at 16:21
So in the image you provided of your console, it shows the contents of `markerPlaces`. It only has one element, and that element doesn't contain a `lat` variable. That's what is returning undefined. – Matt Oct 23 '14 at 16:39
you mean the first or the second image? – ghost Oct 23 '14 at 16:56

printing value from Javascript Object

1 Answers1