Here is the page-level script code to do this:







The first script uses Google's gears object (used in Chrome, for
example) which stores the browser's geolocation information. The second
script is an implementation that looks for different device types and
handles the "quirks". The inline third script simply implements all the
above and populates two hidden fields with the latitude and longitude.
Since I am using the Artem.GoogleMap server control in this case, we have
to trigger a postback to get the control to render a map.

Now what if none of this works? Let's have a look at the ASP.NET page
codebehind:

protected void Page_Load(object sender, EventArgs e)
{
if (!String.IsNullOrEmpty(Lat.Value) &&
!String.IsNullOrEmpty(Lng.Value))
{
double latitude = double.Parse(Lat.Value);
double longitude = double.Parse(Lng.Value);
var request = new GeoRequest(latitude, longitude);
var response = request.GetResponse();
if (response.Status == GeoStatus.OK)
{
FormattedAdr.Text =
response.Results[0].FormattedAddress;
map1.Address = FormattedAdr.Text;
}
}

else
{
var loc = GEOIP.GeoLocation.GetLocation();
map1.Latitude = loc.Latitude;
map1.Longitude = loc.Longitude;
FormattedAdr.Text = loc.City + " " + loc.Region + " " +
loc.PostalCode;
map1.DataBind();
}
}

You can see above that if the hidden fields are not empty, we issue a
GoogleGeocoding request and map the coordinates. And, if that fails, I use
the free MaxMind Geolocation javascript API, but I do this server-side as
follows:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;

namespace GEOIP
{
public static class GeoLocation
{

public static Location GetLocation()
{
try
{
WebClient wc = new WebClient();
string s = wc.DownloadString("
http://j.maxmind.com/app/geoip.js");
wc.Dispose();
/* SAMPLE
function geoip_country_code() { return 'US'; }
function geoip_country_name() { return 'United States'; }
function geoip_city() { return 'Deland'; }
function geoip_region() { return 'FL'; }
function geoip_region_name() { return 'Florida'; }
function geoip_latitude() { return '29.0575'; }
function geoip_longitude() { return '-81.3344'; }
function geoip_postal_code() { return ''; }
function geoip_area_code() { return '386'; }
function geoip_metro_code() { return '534'; } */

s = s.Replace("function geoip_country_code() { return '", ""
);
s = s.Replace("function geoip_country_name() { return '", ""
);
s = s.Replace("function geoip_city() { return '", ""
);
s = s.Replace("function geoip_region() { return '", ""
);
s = s.Replace("function geoip_region_name() { return '", ""
);
s = s.Replace("function geoip_latitude() { return '", ""
);
s = s.Replace("function geoip_longitude() { return '", ""
);
s = s.Replace("function geoip_postal_code() { return '", ""
);
s = s.Replace("function geoip_area_code() { return '", ""
);
s = s.Replace("function geoip_metro_code() { return '", ""
);
s = s.Replace("'; }", "");
string[] s2 = s.Split("
".ToCharArray());


Location loc = new Location();
loc.CountryCode = s2[0];
loc.CountryName = s2[1];
loc.City = s2[2];
loc.Region = s2[3];
loc.RegionName = s2[4];
loc.Latitude = double.Parse(s2[5]);
loc.Longitude = double.Parse(s2[6]);
loc.PostalCode = s2[7];
loc.AreaCode = s2[8];
loc.MetroCode = s2[9];
return loc;
}
catch
{
return null;
}
}
}
}

public class Location
{
public string CountryCode { get; set; }
public string CountryName { get; set; }
public string City { get; set; }
public string Region { get; set; }
public string RegionName { get; set; }
public double Latitude { get; set; }
public double Longitude { get; set; }
public string PostalCode { get; set; }
public string AreaCode { get; set; }
public string MetroCode { get; set; }

}

The result is that we can get a map for virtually any browser or device.

http://eggheadcafe.com/FileUpload/1145921998_GeoLocation.zip