While Microsoft have released their new Virtual Earth ASP.NET Control, I still haven't found a decent wrapper that converts addresses to langitude and longitude co-ordinates.  There is a Geo coder web service available here (this shows the co-ordinates for the White House) but it seems to only work for US addresses, which doesn't help me at all.

So for the moment, I'm still using Google Maps, and have prepared the following to show you how to integrate Google Maps into your ASP.NET pages.

Demo | Code

Step 1. Get a Google Maps API key

In order to use Google Maps on your site, you need to register for a free Google Maps API key from here: http://www.google.com/apis/maps/

Step 2. Download the SubGurim Google Maps wrapper dll

This one is the best Google Maps wrapper I have found so far http://en.googlemaps.subgurim.net/descargar.aspx.  It is a commercial product (from $10), or you can put up with the overlayed text in the free versions.

Download the gmaps.dll file and add it to your \bin directory.

Step 3. Set up your aspx page

In your aspx page, add a few text boxes to gather the address details.  You can simply use one textbox, or split the address to enable validation for suburbs, countries, etc.  I haven't included any form validation in my example.

<p style="text-align:right; margin-right:300px">
    Street Address: 
    <asp:textbox ID="txtStreetAddress" runat="server" Width="150px" /><br />
    Suburb: 
    <asp:textbox ID="txtSuburb" runat="server" Width="150px" /><br />
    Country: 
    <asp:textbox ID="txtCountry" runat="server" Width="150px" /><br /><br />
    <asp:Button Text="Show Map" ID="lnkShowMap" runat="server" />
</p>

You need to add your Google API key to your web.config file like so:

<appSettings>
    <add key="googlemaps.subgurim.net" value="YourGoogleMapsAPIKeyHere" />
</appSettings>

And finally, you need to register the SubGurim wrapper at the top of your page (or in your web.config if you have a number of pages that display maps):

<%@ Register Assembly="GMaps" Namespace="Subgurim.Controles" TagPrefix="cc1" %>

Step 4: Add code to display the map

Finally, add code that collates your address fields and calls the Google Maps wrapper.

Protected Sub lnkShowMap_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Handles lnkShowMap.Click
    Dim strFullAddress As String
    Dim sMapKey As String = 
    ConfigurationManager.AppSettings("googlemaps.subgurim.net")
    Dim GeoCode As Subgurim.Controles.GeoCode

    ' Combine our address fields to create the full address.  The street, 
    ' suburb and country should be seperated by  periods (.)
    strFullAddress = txtStreetAddress.Text & ". " & txtSuburb.Text
        & ". " & txtCountry.Text

    ' Work out the longitude and latitude
    GeoCode = GMap1.geoCodeRequest(strFullAddress, sMapKey)
    Dim gLatLng As New Subgurim.Controles.GLatLng(GeoCode.Placemark.coordinates.lat, 
        GeoCode.Placemark.coordinates.lng)
    ' Display the map
    GMap1.setCenter(gLatLng, 16, Subgurim.Controles.GMapType.GTypes.Normal)
    Dim oMarker As New Subgurim.Controles.GMarker(gLatLng)
    GMap1.addGMarker(oMarker)
End Sub

That's it! Check out the demo or download the source code, and let me know if you find a good wrapper for the Virtual Earth ASP.NET control!

Bartek