I recently implemented a newsletter subscription form in ASP.NET (2.0) for the CGIAR Secretariat on behalf of CGNET. This is the second project I’ve done in ASP.NET for CGIAR. I’ve never considered myself a skilled ASP developer and like many, picked up my ASP skills based on code I’d seen on the intertubes and via transfer from related languages. In other words, prior to this project, I was a somewhat capable ASP spaghetti coder.
Tired of producing mediocre code and eager to learn what this whole .Net thing was all about, I decided to invest some time learning how to write better ASP and take advantage of as many features of .Net as I could. Armed with two really good books on the subject (Beginning ASP.NET 3.5 in C# and VB and Programming ASP.NET 3.5, 4th Edition), I learned a lot about the .Net revolution and in the end I significantly improved the quality of my code.
DOT.NET borrows heavily from other MVC-like frameworks. I was surprised by the number of similarities between the ASP.NET-way of doing things and the Fusebox-way of doing things. The rest of this post examines some of these similarities and other aspects of working with ASP.NET. This is mostly an examination of ASP.NET from a (PHP) Fusebox developers point of view.
The CGIAR Secretariat is responsible for www.cgiar.org. The CGIAR Newsroom is one of the primary
sections of their web site. It includes an aggregate RSS news feed of all news items coming out of many of the CGIAR centers. Since many people still are unaware of the advantages of RSS, the CGIAR Secretariat asked if we could set up a system that would allow people to subscribe to the feed via email. Specifically, the system we set up allows people to subscribe and/or unsubscribe via cgiar.org which then automatically sends periodic emails of recently added news items (as they’re added, of course).
The Bottom Line
As an “experienced” web application developer I very much appreciated the ASP.NET-way of doing things. There was nothing in this project that ASP.NET wasn’t able to handle elegantly and more or less efficiently. The project consisted of implementing the following features:
- A public subscribe and unsubscribe form with CAPTCHA
- A nightly script that produces a notification email, with alternate views (plain text and html), consisting of news items that had not been sent in prior emails (which implies keeping track of what’s been sent and what hasn’t)
A password protected administration interface
The entire project was completed in about 80 hours (including an initial version of the administration interface which was later tabled).
If given the choice of doing the same project in PHP Fusebox, assuming I had the same knowledge and experience with PHP that I had with ASP when I started, would I have chosen PHP Fusebox over ASP.NET? Maybe…
One of the goals of any application framework is to maximize code reuse (and conversely, minimize code duplication). Functions (methods) are one example of how this is accomplished, but when it comes to the presentation level, developers often find they need a more powerful programming model. Both ASP.NET and Fusebox (and many other web application frameworks) provide tools
capable of complete solutions. In ASP.NET, a Master Page is a template for all the pages of a site although its functionality goes beyond a simple templating engine. Master Pages also let you define “behaviors” common to all pages, similar, somewhat, to the Fusebox 3 fbx_Settings file or the Fusebox 4 fusebox.init file.
A powerful templating engine will frequently go beyond “one layer” and allow the developer to subdivide sections of the Master to be handled by other parts of the application. ASP.NET offers this functionality directly and at least one project I’ve worked on in Fusebox had the same functionality. I found a few opportunities to use this feature on this project.
Fusebox does not offer a templating engine out of the box, but you can easily create much of this capability in Fusebox 4 (and to some degree in Fusebox 3) using Content Variables and a “layout” circuit. Most projects I work on offer some such circuit.
In the end I got a lot of milage out of Master Pages for this project and hope to be able to use them in future projects for CGIAR.
By default, every ASP.NET page contains a form that executes on the server. The value of the “action” attribute for the form is the current file. Microsoft has termed this approach “postback” because you post the form back to the same document that created it. In some respects this is similar to the Fusebox implementation of the Front Controller design pattern, where every request is for the same server-side script (e.g.: /index.php) followed by a Query String containing directions on what files, functions, and procedures to execute.
ASP.NET offers the developer server-side elements knows as panels. Panels are “controls” (elements?) that contain other controls. By setting the visible property of a panel you can control whether or not its contents are visible on the page. For the CGIAR project mentioned above, I used this technique to display either the subscription form or the “thank you” message following a successful subscription. I suppose that, if each ASP.NET page is the equivalent of a Fusebox circuit, that each panel could be the equivalent of a Fuseaction. You would simply set the display for all for all of them to false (except the default fuseaction 😉 ) and then display them as needed. Coming from Fusebox, I found the concept very easy to grasp.
Microsoft made an attempt to separate application logic from presentation with DOT.NET. In my opinion, they succeeded.
In order to minimize the amount of raw code found in HTML, .Net provides something known as “code-behind” pages, which are essentially includes with the same name as the file they are attached to. The idea is that your application code goes in the code-behind page and if you need to modify the presentation (the HTML) from within the application code, you do so by referencing elements in your HTML page via their ID attribute (this is an oversimplification but summarizes the approach).
Fusebox, on the other hand, tries to separate code by prefixing file names with one of dsp_, qry_, act_ (and sometimes lyt_).
- qry_ files contain datasource queries and (usually) return some sort of object or array echoed to the browser by a dsp_ file.
- act_ files are for those instances in which you need process data prior to executing a query or echoing to the browser.
- lyt_ files are, in essence, the same as Master Pages in ASP.NET.
In ASP.NET the “HTML” files contain a LOT of .Net namespaced elements. This means the files can be completely valid XHTML (with the single, notable exception of the Processing Instructions found at the top of each page). The benefit is that these files are suddenly very portable and can be consumed by any system capable of reading XML.
If you wanted to reproduce this ASP.NET functionality in Fusebox, you would need to write a plug-in that parses the dsp_ files looking for <fbx: elements and responds accordingly. You could put all of your code in act_ files which would essentially turn them into code-behind files. Now there’s a potential open source time sucker!
As one would expect, the data controls are very complete, but figuring out how to do something like
nesting GridViews was not obvious and were it not for a Nested GridView walk-through article on MSDN, I never would have been able to figure out how to do it. Furthermore, I’m not convinced executing sql on EVERY ROW of a record set is really a good idea (the authors of the walk-through admit this is not the best approach, but only as it concerns caching…).
Much of the CGIAR Newsroom revolves around their RSS feed (which is a compilation of feeds from all of the CGIAR Centers). ASP.NET 2.0 and above include controls for using XML as a data source and thus facilitating the display of XML data in a web page.
Unfortunately, in version 2.0 of .Net (and possibly higher), using XML as a data source only allows you to display the data. It does not allow you to use the built-in INSERT, UPDATE, and DELETE
features of the GridView control. There are work-arounds for implementing this missing functionality but I have to wonder if you save any time hacking in the functionality vs. building the entire administration interface the “old” way (which can be done pretty quickly using XSLT). By my estimates, it’s a draw, at best.
For my needs, web controls, validation in particular, significantly reduce web application development time. I simply cannot express how much I like the validation controls and WISH PHP had something similar!
IntelliSense greatly speeds up coding – Microsoft offers several free (web) application development tools that work quite well and are more than adequate for the projects I usually work on and many include IntelliSense.
I don’t think I could have completed this project as quickly without IntelliSense.
ASP.NET Ambiguities and Disadvantages
Since no language is free of sin, here is my list of things that got the best of me while working on this project:
- web.config cannot be part of code repository since it is machine dependent. If application configuration options are so different between deployment environments, then maybe the author of the application should consider using a different development environment. I would prefer to have the application configuration code right in the application tucked into code that “sniffs” the environment and configures accordingly. This makes for MUCH more portable code.
- .Net developers frequently publish their source code, but it usually needs to be compiled so unless you’re into that or have the time to learn how to do it (and do it right), you won’t find the same kind of huge Open Source community of code that exists for PHP
- ASP.NET 2.0 includes some Authentication and Authorization controls, but like most stuff like this, you have to do things the ASP.NET-way or you can’t use these controls. In other words, there is no (apparent) way to retrofit these controls onto existing authentication mechanisms. In the end this is probably a good thing since most existing authentication methods are not very secure, but in the real world most clients simply are not willing to put money into changing existing systems unless you can clearly demonstrate they are broken.
- One of the main complaints of Fusebox 4 was the XML files. Rather than being used simply for configuration, you could easily add business logic to them. More than one programmer has asked herself: “Why bother with XML to represent classes? Why not just use classes directly?” I must say, when programming in ASP.NET, I often feel like I’m simply setting application configuration parameters which, for anything but the most basic interactions, makes programming harder (and possibly more time-consuming) rather than easier (and faster) since you have to have a clear understanding of what state the application is in at the exact point where your code appears. This can be harder than it seems.
In the end, if I had to do it all over again (and had the choice), I would probably stick with PHP Fusebox but I’m grateful I had the opportunity to improve my knowledge ASP.NET and I wish the CGIAR Secretariat the best with their new system.
Additional Reading and Links
Convert ASP.NET applications into real MVC frameworks
Comparison of Web Application Frameworks