ASP.NET Introduction
ASP.NET is the latest version of Microsoft's Active Server Pages technology (ASP).
What You Should Already Know?
Before you continue you should have a basic understanding of the following:
WWW, HTML, XML and the basics of building Web pages
Scripting languages like JavaScript or VBScript
The basics of server side scripting like ASP or PHP
What is Classic ASP?
Microsoft's previous server side scripting technology ASP (Active Server Pages) is now often called classic ASP.
ASP 3.0 was the last version of the classic ASP.
ASP.NET is Not ASP
ASP.NET is the next generation ASP, but it's not an upgraded version of ASP.
ASP.NET is an entirely new technology for server-side scripting. It was written from the ground up and is not backward compatible with classic ASP.
What is ASP.NET?
ASP.NET is a server side scripting technology that enables scripts (embedded in web pages) to be executed by an Internet server.
.ASP.NET is a Microsoft Technology
.ASP stands for Active Server Pages
.ASP.NET is a program that runs inside IIS
.S (Internet Information Services) is Microsoft's Internet server
.IIS comes as a free component with Windows servers
.IIS is also a part of Windows 2000 and XP Professional
.You can read more about the differences between ASP and ASP.NET in the next chapter of this tutorial.
.ASP.NET is the major part of the Microsoft's .NET Framework.
What is an ASP.NET File?
An ASP.NET file is just the same as an HTML file
An ASP.NET file can contain HTML, XML, and scripts
Scripts in an ASP.NET file are executed on the server
An ASP.NET file has the file extension ".aspx"
How Does ASP.NET Work?
When a browser requests an HTML file, the server returns the file
When a browser requests an ASP.NET file, IIS passes the request to the ASP.NET engine on the server
The ASP.NET engine reads the file, line by line, and executes the scripts in the file
Finally, the ASP.NET file is returned to the browser as plain HTML
What is ASP+?
ASP+ is the same as ASP.NET.
ASP+ is just an early name used by Microsoft when they developed ASP.NET.
The Microsoft .NET Framework
The .NET Framework is the infrastructure for the Microsoft .NET platform.
The .NET Framework is an environment for building, deploying, and running Web applications and Web Services.
Microsoft's first server technology ASP (Active Server Pages), was a powerful and flexible "programming language". But it was too code oriented. It was not an application framework and not an enterprise development tool.
The Microsoft .NET Framework was developed to solve this problem.
NET Frameworks keywords:
Easier and quicker programming
Reduced amount of code
Declarative programming model
Richer server control hierarchy with events
Larger class library
Better support for development tools
The .NET Framework consists of 3 main parts:
Programming languages:
C# (Pronounced C sharp)
Visual Basic (VB .NET)
J# (Pronounced J sharp)
Server technologies and client technologies:
ASP .NET (Active Server Pages)
Windows Forms (Windows desktop solutions)
Compact Framework (PDA / Mobile solutions)
Development environments:
Visual Studio .NET (VS .NET)
Visual Web Developer
This tutorial is about ASP.NET.
ASP.NET 2.0
ASP.NET 2.0 improves upon ASP.NET by adding support for several new features.
You can read more about the differences between ASP.NET 2.0 and ASP.NET in the next chapter of this tutorial.
ASP.NET 3.0
ASP.NET 3.0 is not a new version of ASP.NET. It's just the name for a new ASP.NET 2.0 framework library with support for Windows Presentation Foundation, Windows Communication Foundation, Windows Workflow Foundation; and Windows CardSpace.
You and your users can design dashboards, reports, charts, and models in Excel rather than hard to learn developer tools and you can easily deploy them with SpreadsheetGear for .NET.
ASP.NET has better language support, a large set of new controls and XML based components, and better user authentication.
ASP.NET provides increased performance by running compiled code.
ASP.NET provides increased performance by running compiled code.
ASP.NET code is not fully backward compatible with ASP.
New in ASP.NET
Better language support
Programmable controls
Event-driven programming
XML-based components
User authentication, with accounts and roles
Higher scalability
Increased performance - Compiled code
Easier configuration and deployment
Not fully ASP compatible
Language Support
ASP.NET uses the new ADO.NET.
ASP.NET supports full Visual Basic, not VBScript.
ASP.NET supports C# (C sharp) and C++.
ASP.NET supports JScript as before.
ASP.NET Controls
ASP.NET contains a large set of HTML controls. Almost all HTML elements on a page can be defined as ASP.NET control objects that can be controlled by scripts.
ASP.NET also contains a new set of object oriented input controls, like programmable list boxes and validation controls.
A new data grid control supports sorting, data paging, and everything you expect from a dataset control.
Event Aware Controls
All ASP.NET objects on a Web page can expose events that can be processed by ASP.NET code.
Load, Click and Change events handled by code makes coding much simpler and much better organized.
ASP.NET Components
ASP.NET components are heavily based on XML. Like the new AD Rotator, that uses XML to store advertisement information and configuration.
Differences between ASP and ASP.NET
ASP.NET has better language support, a large set of new controls and XML based components, and better user authentication.
ASP.NET has better language support, a large set of new controls and XML based components, and better user authentication.
ASP.NET provides increased performance by running compiled code.
ASP.NET code is not fully backward compatible with ASP.
New in ASP.NET
Better language support
Programmable controls
Event-driven programming
XML-based components
User authentication, with accounts and roles
Higher scalability
Increased performance - Compiled code
Easier configuration and deployment
Not fully ASP compatible
Language Support
ASP.NET uses the new ADO.NET.
ASP.NET supports full Visual Basic, not VBScript.
ASP.NET supports C# (C sharp) and C++.
ASP.NET supports JScript as before.
ASP.NET Controls
ASP.NET contains a large set of HTML controls. Almost all HTML elements on a page can be defined as ASP.NET control objects that can be controlled by scripts.
ASP.NET also contains a new set of object oriented input controls, like programmable list boxes and validation controls.
A new data grid control supports sorting, data paging, and everything you expect from a dataset control.
Event Aware Controls
All ASP.NET objects on a Web page can expose events that can be processed by ASP.NET code.
Load, Click and Change events handled by code makes coding much simpler and much better organized.
ASP.NET Components
ASP.NET components are heavily based on XML. Like the new AD Rotator, that uses XML to store advertisement information and configuration.
User Authentication
ASP.NET supports forms-based user authentication, including cookie management and automatic redirecting of unauthorized logins.
User Accounts and Roles
ASP.NET allows for user accounts and roles, to give each user (with a given role) access to different server code and executables.
High Scalability
Much has been done with ASP.NET to provide greater scalability.
Server to server communication has been greatly enhanced, making it possible to scale an application over several servers. One example of this is the ability to run XML parsers, XSL transformations and even resource hungry session objects on other servers.
Compiled Code
The first request for an ASP.NET page on the server will compile the ASP.NET code and keep a cached copy in memory. The result of this is greatly increased performance.
Easy Configuration
Configuration of ASP.NET is done with plain text files.
Configuration files can be uploaded or changed while the application is running. No need to restart the server. No more metabase or registry puzzle.
Easy Deployment
No more server restart to deploy or replace compiled code. ASP.NET simply redirects all new requests to the new code.
Compatibility
ASP.NET is not fully compatible with earlier versions of ASP, so most of the old ASP code will need some changes to run under ASP.NET.
To overcome this problem, ASP.NET uses a new file extension ".aspx". This will make ASP.NET applications able to run side by side with standard ASP applications on the same server
What You Need
A Windows Computer
ASP.NET is a Microsoft technology. To run ASP.NET you need a computer capable of running Windows.
Windows 2000 or XP
If you are serious about developing ASP.NET applications you should install Windows 2000 Professional or Windows XP Professional.
In both cases, make sure you install the Internet Information Services (IIS) from the Add/Remove Windows components dialog.
Service Packs and Updates
Before ASP.NET can be installed on your computer, it is necessary to have all relevant service packs and security updates installed.
The easiest way to do this is to activate your Windows Internet Update. When you access the Windows Update page, you will be instructed to install the latest service packs and all critical security updates. For Windows 2000, make sure you install Service Pack 2. I will also recommend that you install Internet Explorer 6.
Read the note about connection speed and download time at the bottom of this page.
Remove Your Beta Version
If you have a Beta version of ASP.NET installed, we recommend that you completely uninstall it. Or even better: start with a fresh Windows 2000 or XP installation.
Install .NET
From your Windows Update you can now select to install the Microsoft .NET Framework.
After download, the .NET framework will install itself on your computer - there are no options to select for installation.
You should now be ready to develop your first ASP.NET application!
The .NET Software Development Kit
If you have the necessary bandwidth to download over 130 MB, you might consider downloading the full Microsoft .NET Software Development Kit (SDK).
We fully recommend getting the SDK for learning more about .NET and for the documentation, samples, and tools included.
Connection Speed and Download Time
If you have a slow Internet connection, you might have problems downloading large files like the service packs, the SDK and the latest version of Internet Explorer.
If download speed is a problem, our best suggestion is to get the latest files from someone else, from a colleague, from a friend, or from one of the CDs that comes with many popular computer magazines. Look for Windows 2000 Service Pack 2, Internet Explorer 6, and the Microsoft .NET Framework.
A simple ASP.NET page looks just like an ordinary HTML page.
Hello W3Schools
To start learning ASP.NET, we will construct a very simple HTML page that will display "Hello W3Schools" in an Internet browser like this:
Hello W3Schools!
Hello W3Schools in HTML
This code displays the example as an HTML page:
Hello W3Schools!
If you want to try it yourself, save the code in a file called "firstpage.htm", and create a link to the file like this: firstpage.htm
Hello W3Schools in ASP.NET
The simplest way to convert an HTML page into an ASP.NET page is to copy the HTML file to a new file with an .aspx extension.
This code displays our example as an ASP.NET page:
Hello W3Schools!
If you want to try it yourself, save the code in a file called "firstpage.aspx", and create a link to the file like this: firstpage.aspx
How Does it Work?
Fundamentally an ASP.NET page is just the same as an HTML page.
An HTML page has the extension .htm. If a browser requests an HTML page from the server, the server sends the page to the browser without any modifications.
An ASP.NET page has the extension .aspx. If a browser requests an ASP.NET page, the server processes any executable code in the page, before the result is sent back to the browser.
The ASP.NET page above does not contain any executable code, so nothing is executed. In the next examples we will add some executable code to the page to demonstrate the difference between static HTML pages and dynamic ASP pages
.
Classic ASP
Classic ASP
Active Server Pages (ASP) has been around for several years. With ASP, executable code can be placed inside HTML pages.
Previous versions of ASP (before ASP .NET) are often called Classic ASP.
ASP.NET is not fully compatible with Classic ASP, but most Classic ASP pages will work fine as ASP.NET pages, with only minor changes.
If you want to learn more about Classic ASP, please visit our ASP Tutorial.
Dynamic Page in Classic ASP
To demonstrate how ASP can display pages with dynamic content, we have added some executable code (in red) to the previous example:
Hello W3Schools!
<%Response.Write(now())%>
The code inside the <% --%> tags is executed on the server.
Response.Write is ASP code for writing something to the HTML output stream.
Now() is a function returning the servers current date and time.
If you want to try it yourself, save the code in a file called "dynpage.asp", and create a link to the file like this: dynpage.asp
Dynamic Page in ASP .NET
This following code displays our example as an ASP.NET page:
Hello W3Schools!
<%Response.Write(now())%>
If you want to try it yourself, save the code in a file called "dynpage.aspx", and create a link to the file like this: dynpage.aspx
ASP.NET vs Classic ASP
The previous examples didn't demonstrate any differences between ASP.NET and Classic ASP.
As you can see from the two latest examples there are no differences between the two ASP and ASP.NET pages.
In the next chapters you will see how server controls make ASP.NET more powerful than Classic ASP.
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