2

I'm looking for an article that will dive deep into how ASP.NET works and how it renders controls from XML markup. For example, under the hood, how does ASP.NET take the following markup and have it produce the results we see?

<asp:Label ID="MyLabel"><%= myObject.Text%></asp:Label>

Does anybody know of any article that will dive deep into the inner workings of ASP.NET?

Improve this question
3
  • are you asking how web server controls are rendered as html tags? Commented Jun 12, 2009 at 0:24
  • Basically, I'm asking my question in a roundabout way. I'm building something that automatically reads markup from an XML file and generates something that slightly resembles a WebForm with contorls. I'm don't know why, but I generally struggle with parsing XML and I'm hoping that understanding more about how ASP.NET parses ASPX pages, I'll be able to better understand how to implement what I would like to accomplish. Commented Jun 12, 2009 at 0:29
  • Google (or Bing!) "asp.net page lifecycle". I think that's what you are looking for. Commented Jun 12, 2009 at 2:38

4 Answers 4

Reset to default
6

What happens "under the hood" is that each ASP.NET page is compiled into a .NET class, just like any other. Controls (ASCX) are compiled the same way. There is a compiler for ASP.NET markup just like there is a compiler for c# and VB.NET - you can think of the ASP.NET markup as "yet another" language which compiles to native MSIL.

The native ASP.NET markup is handled by the PageParser. You may notice this class has one interesting and very useful method - GetCompiledPageInstance. As it implies, it compiles the page to a native .NET class. This can be overridden (e.g., you could come up with your own markup and write your own parser/compiler). Spark is a popular alternative to ASP.NET markup.

Each class ultimately inherits from Page or Control. Both of these classes have Render() methods which, at the end of the class's executing its custom functionality you have implemented, write HTML to an output stream.

The big difference is that the compilation often happens at a much different time than the c# or VB.NET code. This is not really a technical requirement so much as it is a feature that permits decoupling the presentation .NET language from the functional .NET language. ASPX and ASCX pages are compiled by the ASP.NET runtime when they are requested in the context of a web server. The compiled assemblies are then held in memory until a) the web application shuts down or b) a filesystem change is detected in one of the ASPX files, triggering a recompile.

It is possible to compile your ASPX pages alongside your c#/VB.NET/whatever, so you can deploy the entire application as a single assembly. This has two advantages - one, the obvious ease of deploying a single DLL. Second, it eliminates the LOOOONG wait time that so often accompanies a "first hit" to an ASP.NET web application. Since all the pages are precompiled, the assembly simply needs to be loaded into memory upon first request, instead of compiling each file.

Improve this answer
Sign up to request clarification or add additional context in comments.

Comments

2

Reflector -> Expand System.Web.UI -> PageParser Class -> decompile -> Enjoy

(Sorry, not trying to be snarky; this is the only way I was able to get a grasp of it myself)

Improve this answer

2 Comments

Whoa, since when did encouraging people to use reflector go out of style?
I just used .NET Reflector to determine why an HtmlLink tag was mangling the href value during rendering. Being able to look under the covers is an incredibly powerful tool to have in your bag.
0

I always like this site...

https://web.archive.org/web/20210304122759/https://www.4guysfromrolla.com/articles/050504-1.aspx (overview)

https://web.archive.org/web/20210411013534/http://www.4guysfromrolla.com/articles/011404-1.aspx (more in-depth)

Improve this answer

Comments

-1

I need a LMBTFY (Let me Bing that for you). ;P

Anyway, here are some pages:

Compilation and Deployment in ASP.NET 2.0
Inside the ASP.NET 2.0 Code Compilation Model

Improve this answer

Comments

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.