Avoid Javascript if you can!

If you're developing a rich web control, then -- no two ways about it -- you are stuck using JavaScript. If you're developing a business web app, avoid JavaScript at (nearly) all costs.

Now before you assume that I'm an ignorant wretch who's never really used JavaScript, let me tell you this. I've done a bit of client-side in my time. Including: A Mac OS X widget written with no JS framework, a jQuery plugin for filtering search results (written for and included in jqGrid since 3.5), and lots of custom code for various projects using jQuery or Prototype.

This is what clinched it for me: When I was doing a refactor of a particular piece of my main work project, I decided to fully embrace jQuery and use its UI components, themes, plugins, etc. The long and the short of it is that I will never do this again.

I mean, it's cool that you can create a snazzy jQuery UI widget with a div and a line of javascript, but making that work with your server-side language requires javascript glue. Even with jQuery making things easier, I had to write an inane amount of JS code to glue everything together (check or toggle css classes, setup and handle events like clicking, make ajax requests). My application was a tad complicated, and this was not helped by the fact that I now had to debug both client and server code (and the server code being the much easier part). Sometimes it's fun to make your own glue, but it's a massive expense just to have a pretty client-side control.

The take-away from this is that as an app developer (not a control developer) it's best to avoid using client-side code (Javascript) when possible. I can get around this in ASP .NET for the most part by using pre-made AJAX server controls from the Ajax Control Toolkit, or by using normal server-side controls in UpdatePanels. UpdatePanels potentially add a good bit of overhead, but for internal projects (which is most of what I do) having slightly better performance is not nearly worth the time it takes to make high performance glue.

Well, that's my perspective anyway. ;)