Particularly in a means of moving PowerBuilder applications to the web. What I’m looking for doesn’t require a server license or the installation of unmanaged code to the web server, and works well across different browsers (not just Internet Explorer). The WPF DataWindow will help move us to a place where we won’t need to deploy unmanaged code. But I’m doubtful that the current WebForms implementation will ever get us to a place where we are browser independent. Not that I have any doubts about the technical capabilities of the Sybase engineering staff. It’s just a cold hard fact that there are too many inconsistencies in the way that various browsers render HTML/JavaScript based pages for us to expect any solution to work that doesn’t require hand tweaking to ensure adequate results across multiple browsers. And cross-browser support is becoming increasingly important. According to http://marketshare.hitslink.com, Internet Explorer only has 72% market share. Firefox is at 20%, Safari at 6%. Google Chrome is still in beta, and only shows a > 1% market share, but I expect it to take off once (if ever) it leaves beta.

What might get us there? I see two potential approaches. One would be to take the WPF capability that Sybase is planning to provide in PowerBuilder 12, and deploy that via XBAP.(XAML Browser Applications). If you try out the weathernews XBAP app (http://weathernews.com/wpfglobal.xbap) in both Internet Explorer and Firefox, it looks identical. I managed to get it functioning under Google Chrome by copying over some of the Firefox runtime files. I couldn’t get it to work under Safari at all though.

The other approach would be Silverlight. Now although Silverlight and WPF are both based on XAML, they aren’t equivalent. I was under the impression that Silverlight (formerly WPF/E) was a subset of WPF. They actually differ significantly. For more information, you might see “Code reuse in WPF and Silverlight 2” (http://xrl.us/osafu), which provides an explanation of the issues associated with sharing code between Silverlight and WPF. Some of the other differences are highlighted in an article entitled “Silverlight Problems That Affect Me” (http://xrl.us/osafo). Silverlight is designed to not only be browser independent, but platform independent as well. What’s interesting about that is that, as “Program Silverlight with the CoreCLR” (http://xrl.us/or9o9) point out, is that there are runtimes in the works for Linux and Mac OS X, but for Symbian OS and Windows Mobile. Imagine Silverlight functionality being added into PocketBuilder as well, so that we could eventually deploy to non-Windows Mobile platforms.

I think this later approach makes more sense, and I really believe that Sybase would be well served to focus on it (SilverLight) now rather than WPF. I’ve argued in Sybase’s newsgroups that I don’t believe that Silverlight is currently “ready for prime time”. But by the time Sybase releases PowerBuilder 12, I’m sure it will be. Silverlight is currently in a beta for 2.0. I believe by the time 3.0 is available it should be a prime contender. If Sybase was to focus on deployment to it for PowerBuilder 12.0, they could be ready when Silverlight 3.0 is released.

Why Silverlight over WPF? Mainly because PowerBuilder developers currently have adequate methods of deploying thick-client apps (native PowerBuilder or .Net WinForm). What we lack is an adequate method of deploying thin-client (or rich internet) apps. I’m sure that WinForm will eventually be made obsolete, much the way that Win32 replaced Win16, but it’s going to be quite some time before that happens. Enough time for PowerBuilder to support WPF in the major version after 12.0. We need a better web solution today though. If you look at the message traffic in Sybase’s newsgroups, you’ll see that web apps are where the interest is. We opened up sections of the newsgroups specific to the new .Net target types in June of 2007. Since then (roughly a year and a quarter) there have been 300+ posts for .Net assemblies, 550+ posts for .Net web services, 700+ posts for .Net WinForms and 3000+ posts for .Net WebForms. People are interested in deploying their PowerBuilder applications as web apps, and the current thin-client solution is not (in my opinion) adequate for many people. The rich internet approach that Silverlight provides would serve many of those people better.