Can you add Virtual Earth to your ASP.NET 2.0 applications without writing JavaScript?
Heck yea! Chris Pietschmann wrote a sweet little server control that does it! In his own words "PietschSoft.VE is an ASP.NET 2.0 Virtual Earth Server Control. The goal of this control is to allow ASP.NET developers to utilize Virtual Earth mapping within their applications without requiring any JavaScript knowledge." The full source code for the control is available at http://www.codeplex.com/PietschSoftVE3.
I discovered the control while I was building my own for my Virtual Earth demos. I have heard plenty of feedback from customers who don't want to write JavaScript. Currently, the control uses the traditional "full postback" model used by many ASP.NET server controls. This means that the map and all of it's previous state gets rebuilt on every postback (i.e every interaction with the map requiring execution of server-side code).
The good news is that Chris has decided to release a new version of the control that "will have full support of the ASP.NET AJAX Extensions." I built a proof of concept using the pushpin scenario from the control built by Chris. I reworked it using the ASP.NET AJAX Control Toolkit. If you have seen my Virtual Earth demos, then you've seen the proof of concept.
On the surface, you might think to yourself, "Just drop it in an UpdatePanel." There are known issues with using the current control in an UpdatePanel. However, even if you could, the entire map would be rebuilt on every "behind the scenes" postback intiated by the UpdatePanel/Trigger. Ideally, what you want to do is render the map once. On subsequent partial-page postbacks, you should be able to interact with the control server-side and send down the additional JavaScript needed on the client to incrementally add to the map. The proof of concept I built uses this approach. You can download it here.
DISCLAIMER: This control was written as a "proof of concept" for my demos. It is "AS-IS" and not without bugs;). I didn't really think through all the hard scenarios that Chris will surely encounter. I'm really looking forward to seeing the final product from Chris.
-Marc
