Pinpoint locations on google maps using ASP.NET

Question

I am trying to pinpoint locations on google (or bing) maps, and I'm unable to do so in both. The code structure is similar in both, and I present the google maps attempt:

The objective: I have a linked list of Objects, each of which contain latitude and longitude, all of which have to be pinpointed.

Full ASP: http://pastie.org/7752124 (The repeater is to present the search results)

Relevant (in head):

<script type="text/javascript">
    var map = null;
    function initialize() {
        var mapOptions = {
            center: new google.maps.LatLng(40.42, -98.737),
            zoom: 4,
            mapTypeId: google.maps.MapTypeId.ROADMAP
        };
        map = new google.maps.Map(document.getElementById("map-canvas"),
        mapOptions);
        //pushPin(25, 80);
    }
    function pushPin(lat, lon) {
        alert(lat + " " + lon);
        var myLatlng = new google.maps.LatLng(lat, lon);
        var marker = new google.maps.Marker({
            position: myLatlng,
            map: map,
            title: "Hello World!"
        });
    }
    google.maps.event.addDomListener(window, 'load', initialize);
</script>

Codebehind: Activated when user clicks the search button:

protected void Button1_Click(object sender, EventArgs e)
    {
        List<Results> rlist = getResults(query);
        String Locations = "";
        foreach (Results res in rlist)
        {
            Page.ClientScript.RegisterStartupScript(
                GetType(),
                "MyKey",
                "pushPin("+res.latitude+","+res.longitude+");",
                true);
        }
        this.rptREsults.DataSource = rlist;
        this.rptREsults.DataBind();
    }

public class Results
{
    public string filename { get; set; }
    public string asciiname { get; set; }
    public string latitude { get; set; }
    public string longitude { get; set; }
}

The results are correct and do contain latitude and longitude, and when I put an alert in the pushPin method, only one alert box comes, but no pinpoint is created. Is there a better way to store and pinpoint a list of Latitudes and Longitudes?

The pushPin method works when I call it from another javascript method.

Answer 1

I tend to do it this way, this is a cut down version/example of some code Im using on another site but should give you enough to get things working:

var markers = new Array();
var markerLatLongs = new Array();
var sites = // JSON formatted version of your Results object(s)

function initialize() {
    var mapOptions = {
      mapTypeId: google.maps.MapTypeId.ROADMAP
    };
    map = new google.maps.Map(document.getElementById('map'),
        mapOptions);


    createMarkers();
}

function createMarkers() {
    for (var j = 0; j < sites.length; j++)
    {
        markerLatLongs[j] = new google.maps.LatLng(sites.latitude ,sites.longitude )
        markers[j] = new google.maps.Marker({
            position: markerLatLongs[j],
            map: map,
            title: sites[j].siteName
        });    
    }
}

In order to solve the timing problem rap your calls to pushPin in another function, then add a call to the function wrapper from within initialize something like this:

protected void Button1_Click(object sender, EventArgs e)
    {
        List<Results> rlist = getResults(query);
        String Locations = "";
        StringBuilder pushPinCalls = new StringBuilder();
        foreach (Results res in rlist)
        {
          pushPinCalls.AppendFormat("pushPin({0},{1});",res.latitude,res.longitude);
        }
            Page.ClientScript.RegisterStartupScript(
                GetType(),
                "MyKey",
                string.Format("function pushPinManager() {{0}}",pushPinCalls.ToString());,
                true);
        this.rptREsults.DataSource = rlist;
        this.rptREsults.DataBind();
    }

and in the js:

function initialize() {
    var mapOptions = {
        center: new google.maps.LatLng(40.42, -98.737),
        zoom: 4,
        mapTypeId: google.maps.MapTypeId.ROADMAP
    };
    map = new google.maps.Map(document.getElementById("map-canvas"),
    mapOptions);
    pushPinManager();
}