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ASP.NET (software)
Initial releaseJanuary 5, 2002; 19 years ago (2002-01-05)
Stable release
4.8 / April 18, 2019; 2 years ago (2019-04-18)[1]
Written in.NET languages
Operating systemMicrosoft Windows, Linux, macOS
TypeWeb framework
LicenseApache License 2.0 Edit this on Wikidata
ASP.NET (file format)
Filename extension.aspx, .cshtml, .vbhtml
Internet media type
Developed byMicrosoft

ASP.NET is an open-source,[2]server-side web-application framework designed for web development to produce dynamic web pages. It was developed by Microsoft to allow programmers to build dynamic web sites, applications and services.

It was first released in January 2002 with version 1.0 of the .NET Framework and is the successor to Microsoft's Active Server Pages (ASP) technology. ASP.NET is built on the Common Language Runtime (CLR), allowing programmers to write ASP.NET code using any supported .NET language. The ASP.NET SOAP extension framework allows ASP.NET components to process SOAP messages.

ASP.NET's successor is ASP.NET Core. It is a re-implementation of ASP.NET as a modular web framework, together with other frameworks like Entity Framework. The new framework uses the new open-source .NET Compiler Platform (codename "Roslyn") and is cross platform. ASP.NET MVC, ASP.NET Web API, and ASP.NET Web Pages (a platform using only Razor pages) have merged into a unified MVC 6.[3]

Programming models

ASP.NET supports a number of programming models for building web applications:[4]

  • ASP.NET Web Forms – A framework for building modular pages out of components, with UI events being processed server-side.
  • ASP.NET MVC – allows for building web pages using the model–view–controller design pattern.
  • ASP.NET Web Pages – A lightweight syntax for adding dynamic code and data access directly inside HTML markup.[5]
  • ASP.NET Web API – A framework for building Web APIs on top of the .NET Framework.[6]
  • ASP.NET WebHooks – Implements the Webhook pattern for subscribing to and publishing events via HTTP.
  • SignalR – A real-time communications framework for bi-directional communication between client and server.

Other ASP.NET extensions include:

  • ASP.NET Handler – Components that implement the System.Web.IHttpHandler interface. Unlike ASP.NET Pages, they have no HTML-markup file, no events and other supporting. All they have is a code-file (written in any .NET-compatible language) that writes some data to the server HTTP response. HTTP handlers are similar to ISAPI extensions.
  • ASP.NET AJAX – An extension with both client-side as well as server-side components for writing ASP.NET pages that incorporate Ajax functionality.
  • ASP.NET Dynamic Data – A scaffolding extension to build data driven web applications.

IIS integrated pipeline

On IIS 6.0 and lower, pages written using different versions of the ASP framework cannot share session state without the use of third-party libraries. This does not apply to ASP.NET and ASP applications running side by side on IIS 7. With IIS 7.0, modules may be run in an integrated pipeline that allows modules written in any language to be executed for any request.[7]

Third-party frameworks

It is not essential to use the standard Web forms development model when developing with ASP.NET. Noteworthy frameworks designed for the platform include:

  • Base One Foundation Component Library (BFC) is RAD framework for building .NET database and distributed computing applications.
  • DotNetNuke is an open-source solution that provides both a web application framework and a content management system that allows for advanced extensibility through modules, skins, and providers.
  • Castle MonoRail, an open-source MVC framework with an execution model similar to Ruby on Rails. The framework is commonly used with Castle ActiveRecord, an ORM layer built on NHibernate.


The ASP.NET releases history tightly correlates with the .NET Framework releases:

Date Version Remarks New ASP.NET related features
January 16, 2002 Old version, no longer maintained: 1.0 First version

released together with Visual Studio .NET

  • Object-oriented Web application development supporting inheritance, polymorphism and other standard OOP features
    • Developers are no longer forced to use Server.CreateObject(...), so early-binding and type safety are possible.
  • Based on Windows programming; the developer can make use of DLL class libraries and other features of the Web server to build more robust applications that do more than simply rendering HTML (e.g., exception handling)
April 24, 2003 Old version, no longer maintained: 1.1 released together with Windows Server 2003

released together with Visual Studio .NET 2003

  • Mobile controls
  • Automatic input validation
November 7, 2005 Old version, no longer maintained: 2.0

codename Whidbey
released together with Visual Studio 2005 and Visual Web Developer Express
and SQL Server 2005

  • New data controls (GridView, FormView, DetailsView)
  • New technique for declarative data access (SqlDataSource, ObjectDataSource, XmlDataSource controls)
  • Navigation controls
  • Master pages
  • Login controls
  • Themes
  • Skins
  • Web parts
  • Personalization services
  • Full pre-compilation
  • New localization technique
  • Support for 64-bit processors
  • Provider class model
November 21, 2006 Old version, no longer maintained: 3.0 Released with Windows Vista
November 19, 2007 Old version, no longer maintained: 3.5 Released with Visual Studio 2008 and Windows Server 2008
  • New data controls (ListView, DataPager)
  • ASP.NET AJAX included as part of the framework
  • Support for HTTP pipelining and syndication feeds.
  • WCF support for RSS, JSON, POX and Partial Trust
  • All the .NET Framework 3.5 changes, like LINQ etc.
August 11, 2008 Old version, no longer maintained: 3.5 Service Pack 1 Released with Visual Studio 2008 Service Pack 1
  • Incorporation of ASP.NET Dynamic Data
  • Support for controlling browser history in an ASP.NET AJAX application
  • Ability to combine multiple JavaScript files into one file for more efficient downloading
  • New namespaces System.Web.Abstractions and System.Web.Routing
April 12, 2010 Old version, no longer maintained: 4.0 Released with Visual Studio 2010

Parallel extensions and other .NET Framework 4 features

The two new properties added in the Page class are MetaKeyword and MetaDescription.

August 15, 2012 Old version, no longer maintained: 4.5 Released with Visual Studio 2012 and Windows Server 2012 for Windows 8

Parallel extensions and other .NET Framework 4.5 features

October 17, 2013 Old version, no longer maintained: 4.5.1 Released with Visual Studio 2013[8] for Windows Server 2012 R2 and Windows 8.1
  • Bootstrap 3.0
  • Web API 2: OAuth 2.0, OData improvements, CORS
  • MVC 5: Attribute routing, authentication filters and filter overrides
  • EF 6
  • SignalR
  • OWIN
May 5, 2014[9] Older version, yet still maintained: 4.5.2
  • Higher reliability HTTP header inspection and modification methods
  • New way to schedule background asynchronous worker tasks
July 20, 2015[9] Older version, yet still maintained: 4.6 Released[10] with Visual Studio 2015[11] and EF 7 Previews for Windows Server 2016 and Windows 10
  • HTTP/2 support when running on Windows 10
  • More async task-returning APIs
November 30, 2015[9] Older version, yet still maintained: 4.6.1
August 2, 2016[9] Older version, yet still maintained: 4.6.2
  • Improved async support (output-cache and session providers)
April 11, 2017[9] Older version, yet still maintained: 4.7 Included in the Windows 10 Creators Update[12]
  • operating system support for TLS protocols
October 17, 2017[9] Older version, yet still maintained: 4.7.1 Included in the Windows 10 Fall Creators Update.[13]
  • Improved accessibility
  • Value tuple types serialization
  • SHA-2 support
April 30, 2018[9] Older version, yet still maintained: 4.7.2
April 18, 2019[9] Current stable version: 4.8 Released[14]
  • JIT and NGEN Improvements
  • Updated ZLib
  • Reducing FIPS Impact on Cryptography
  • Accessibility Enhancements for WinForms
  • Service Behavior Enhancements for WCF
  • High DPI Enhancements, UIAutomation Improvements for WPF
November 18, 2015 Old version, no longer maintained: 5 RC1 This version was later separated from ASP.NET and brought into a new project called ASP.NET Core, whose versioning started at 1.0.[15] An entirely new project with different development tenets and goals
Old version
Older version, still maintained
Latest version
Latest preview version
Future release

Other implementations

The Mono Project supports "everything in .NET 4.5 except WPF, WWF, and with limited WCF and limited ASP.NET 4.5 async stack."[16] ASP.NET can be run with Mono using one of three options: Apache hosting using the mod_mono module, FastCGI hosting, and XSP.

Some top .NET based CMS are: DNN, Sitefinity, Umbraco, Orchard, Kentico, Sitecore and MojoPortal.



  1. ^ "Announcing the .NET Framework 4.8".
  2. ^ "ASP.NET is part of a great open source .NET community". Microsoft. Microsoft. May 14, 2013. Archived from the original on May 11, 2020. Retrieved May 11, 2020.
  3. ^ "Introduction to ASP.NET 5 — ASP.NET 0.0.1 documentation". Archived from the original on May 8, 2020. Retrieved May 11, 2020.
  4. ^ "Choose between ASP.NET and ASP.NET Core".
  5. ^ "ASP.NET Web Pages (Razor) FAQ".
  6. ^ "Get Started with ASP.NET Web API 2 (C#)".
  7. ^ "How to Take Advantage of the IIS 7.0 Integrated Pipeline".
  8. ^ "Announcing release of ASP.NET and Web Tools for Visual Studio 2013".
  9. ^ a b c d e f g h ".net framework product lifecycle".
  10. ^ "Announcing .NET Framework 4.6".
  11. ^ "Visual Studio 2015 and Visual Studio 2013 Update 5 Released". Microsoft.
  12. ^ "Announcing the .NET Framework 4.7".
  13. ^ "Announcing the .NET Framework 4.7.1".
  14. ^ "Announcing the .NET Framework 4.8".
  15. ^ "Releases". GitHub.
  16. ^ "Compatibility | Mono". Compatibility | Mono. 8 September 2015. Archived from the original on 2 July 2016. Retrieved 29 August 2016.

General sources

Edited: 2021-06-18 14:10:51