We have just launched our new Tribute Application for creating customized cards for donations in honour or memory of someone you love.We used Microsoft .NET and the new AJAX library for development of our forms. Our developer teams became enthusiastic supporters of using AJAX styled controls for creating a sense of immediacy in the interface.
However, what was interesting was the new set of bugs that cropped up simply because of now using AJAX controls. Here is an example: the above form has two controls for postal code and zip code and based on which state or province is picked, we flip between them so that you can have client side validation, proper field lengths, etc. Sounds simple enough, but we went through quite a bit of work and bug fixing to make this work.
Here are a few bugs that we found in the process as examples:
1. When you click the back button the right control isn't always displayed.
2. We had styling/layout issues in Mozilla.
3. When you picked a state and then switched to province the value would disappear.
4. The switching of state was generally quite slow on some clients.
In the "old days", the interface would have been really simple - a text box submitted to a server side script. Very few presentation layer bugs because there wasn't really anything going on in the presentation.
So the question becomes - is it really worth it? For Yahoo Mail it might be, but for an average data entry form is it really that crucial?
Now that we're planning phase 2 on our project, I would be much more cautious about going gung-ho on AJAX simply because it dramatically increases the testing/bug fixing time for what amounts to a simple user interface convenience.
