Introduction to ASP.Net from PHP

Question

I am very new to ASP.Net and would like to try this technology, mostly because I am impressed with the performances so far.

I come from the PHP world where you can just include some PHP code into your HTML page and that will do the trick as long as the web server is able to give the page to the PHP processor. One page, one PHP script, this is the rule. (I'm leaving behind path info issues here...)

Now I am very confused about all the ASP.Net tutorials I read so far. ASP.Net seems to be working in many different ways and it looks like history often changed the "best way".

Here what I understood so far:

• You can embed you ASP code within your HTML page, this seems to be the old way, when .Net did not exist. While this looks ok for me PHP guy, I do not understand how I can share classes between pages.
• You can "partially define" (WTF?) the System.Web.UI.Page class and separate the ASP code from the HTML using some events and controls (did not really understand that one).
• You can create controls that you directly embed into your HTML that can be bound to external data, code is then completely separated from the HTML and has to be compiled separately (again, absolutely no clue about that).

Now keep in mind that I am using Mono with Mac OS X, so no Visual Studio, every "use-Visual-Studio-and-everything-is-done-for-you-automatically" answer will be down-voted, I want to actually type my code and understand what is going on under the hood. I want to be able to control what I send to the browser and how.

What would you recommend for a newbie like me to experiment with ASP.Net (using the C# language is that is relevant). Feel free to answer with a long formatted article, I really want an ASP.Net beginner tutorial for existing PHP developers.

Answer 1

You could user Dreamweaver to create your aspx pages.

I started ASP.Net by reading a weekend crash course book which is great to start and to have a basic understanding of an asp.net application. W3Schools might also be a good starting point.

ASP.Net can in some ways be written as you have mentioned, what we can call an inline manner.

Using Visual Studio or Grasshopper will not do everything for you, it will simply setup an empty project for you to modify and build upon.

ASP.Net can also be built in an application manner where the UI is separate from the Business logic and the data access code.

You can embed you ASP code within your HTML page, this seems to be the old way, when .Net did not exist. While this looks ok for me PHP guy, I do not understand how I can share classes between pages.

To Share classes between pages you will need to work in a code behind manner. this means adding class files, which you will then reference in a page directives if you are working in an inline manner. If you are working in a code behind manner then simply use the names spaces to reference the code scopes.

you can find tutorials on Sitepoint.com or other sites such as Codeproject and asp.net tutorials.

You can "partially define" (WTF?) the System.Web.UI.Page class and separate the ASP code from the HTML using some events and controls (did not really understand that one).

This would be Code Behind having the page definition in the aspx file and the code in the aspc.cs file. Asp.net is an event based model where the page get rebuilt on every postback. Once the page is rebuilt the events are fired and the new page state will be saved in the viewstate.

You can create controls that you directly embed into your HTML that can be bound to external data, code is then completely separated from the HTML and has to be compiled separately (again, absolutely no clue about that).

User controls are stored in Ascx files. These are usually built using the code behind technique. They then need to be registered on the host page so that they can then be used.

What I called "partially define" UI.Page to separate ASP code from HTML code is what you call "code behind". I understand that you can put the C# code in a "behind" file but I don't understand how this gives me more control on the HTTP output flow than using inline C# code. – Vincent Robert (3 mins ago)

You may gave greater control due to the page life cycle where you can define custom behaviors for the preInit Init Load PreRender Render and other events. For example, you could override the Render event method and add a footer or to convert the page to a PDF and serve the client a PDF instead of an html page.

About tutorials, the vast majority of tutorials I find either use vocabulary I don't understand (master page, app_code directory, etc.) or just tell how to run the Visual Studio wizard... I need to understand the basics, remember I'm a dumb and limited PHP developer only. – Vincent Robert (1 min ago)

There are two major way of working with ASP.Net Controls, The first is by definint templates and properties in the aspx file and by using wizards. The second can be a mix of defining templates and properties in code and in the aspx file. From the codebehind you can interact with the objects on the aspx page to add custom functionality.

Answer 2

One approach, not the only approach, is to think of ASP.NET and C# as just a better version of PHP. You CAN just use a text editor and your PHP paradigm and create working pages. I did exactly that with my open source app BugTracker.NET.

So, start on mono, with your text editor, on your mac.

After that, the fork in the road for you is do you want to explore what Microsoft had been pushing for a half dozen years, codebehind and webforms, or do you want to explore the hot, new MVC approach. Stackoverflow itself uses MVC.

Answer 3

It is entirely possible to develop ASP.NET web apps using something like TextMate on the Mac. There are two ways to do it:

You can have a file per page and inline the CS/VB code in the ASPX file. C# code goes in script tags with runat="server" Eg:

<% Import Namespace="System.Data" %>
<script runat="server">

protected override void OnInit(EventArgs e)
{
   base.OnInit(e);
}

protected void Page_Load(object sender, EventArgs e)
{
   //on load code goes here
}
</script>

<!-- usual HTML goes in here, including ASP:Server controls -->

Or the preferable approach with a .ASPX page and a ASPX.cs file per page as you have probably seen in the examples.

I mean you could do it this way, then just debug by pointing to Apache (or whatever) and running the code in your web browser. It would work, but it wouldn't be ideal if you are just learning.

Have you looked at MonoDevelop - pretty sure it runs on OSX and would be easier than coding everything by hand

Answer 4

There are usually at least 17 different ways of tackling most problems in asp.net, which does make it somewhat confusing to start with.

If you want to be close to the metal, in a php kind of a way, then inline coding is a good place to start, and will feel the most familiar.

There are many different ways of reusing code in aspnet, from compiling business logic into assemblies(dlls), to putting commonly used chunks of ui into user controls(ascx), which are sort of a cooler version of includes, to name just a couple.
As a starting point for reusing classes, you can put them into the App_Code folder, which is dynamically compiled, so you don't have to think about dlls to start with, or have a go at an ascx file.

The web forms model has advantages in terms of getting things done quickly, but if used indiscriminantly, can produce some horribly bloated markup.

It is a good idea to get a good handle on the page lifecycle, and know where abouts to hook into the request/response cycle.

No, you don't have to use visual studio, but some kind of intellisense and documentation explorer will help a lot. The dotnet framework is huge, and most dotnet developers have suffered OMGWTF moments while learning it, through spending hours writing something that they later found to be already provided somewhere in the framework.

Answer 5

I think the thing that you may really struggle with is a difference in philosophy. The .NET world fundamentally "believes" in object-orientation, while the PHP world has traditionally more emphasized an imperative style of "You go from the top to the bottom and everything you need in the page is either right there or you @require it." OOP definitely introduces more discipline to the way that data and functions are structured and that can be initially off-putting and seem overly rigid. However, most people come to believe that OOP is well worth the learning curve.

Of course, you can define functions and objects in PHP and, if you've been working with those types of PHP capabilities, you'll probably be able to map your experience into ASP.NET more easily. Similarly, you can have imperative dropthrough programming in ASP, but to really achieve the benefits of .NET, you need to develop a comfort with OOP.

Answer 6

One thing worth mentioning here, from someone also coming from php background is a Postback.

A postback is a funcdamental concept in .net and it is essentially a mix of good old server code and Javascript. PHP doesn't have a built-in postback while asp.net does and uses it extensively unless a developer explicitly disables it. Google this term - it may shed some light on page generation issues.

What is it about page generation don't you understand?

Answer 7

Rather belatedly:

Microsoft have a free online course "Learn ASP.NET: for PHP Developers" on their Ramp Up site, part of their learning offering.

These courses usually contain screencasts, articles, sample chapters from books and virtual labs to get you up to speed with the technology stack.