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41-598: 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. In 2016, Microsoft released ASP.NET Core as ASP.NET's successor. This new version

82-561: A COM callable wrapper (CCW). From both the COM and .NET sides, objects using the other technology appear as native objects. See COM Interop . WCF eases a number of COM's remote execution challenges. For instance, it allows objects to be transparently marshalled by value across process or machine boundaries more easily. Windows Runtime ( WinRT ) is a COM-based API, albeit an enhanced COM variant. Because of its COM-like basis, WinRT supports interfacing from multiple programming contexts, but it

123-560: A session that maintains the state of variables from page to page. The Active Scripting engine's support of the Component Object Model enables ASP websites to access functionality in compiled libraries such as dynamic-link libraries . ASP 3.0 does not differ greatly from ASP 2.0 but it does offer some additional enhancements such as Server.Transfer method, Server.Execute method, and an enhanced ASPError object. ASP 3.0 also enables buffering by default and optimized

164-469: A portable C++ header file. Nano-COM extends the native ABI of the underlying instruction architecture and OS to support typed object references – whereas a typical ABI focuses on atomic types, structures, arrays and function calling conventions. A Nano-COM header file defines or names at least three types: Many uses of Nano-COM define two functions to address callee-allocated memory buffers as results: Some implementations of Nano-COM such as Direct3D eschew

205-462: A programming language independent syntax. IDL is similar to C++ with additional syntax for defining interfaces and coclasses. IDL also supports bracketed attributes before declarations to define metadata such as identifiers and relationships between parameters. An IDL file is compiled via the MIDL compiler. For use with C/C++, the MIDL compiler generates a header file with struct definitions to match

246-467: A separation of interface from implementation. This distinction is especially strong in COM where an object has no default interface. A client must request an interface to have any access. COM supports multiple implementations of the same interface, so that clients can choose which implementation of an interface to use. A COM type library defines COM metadata, such as coclasses and interfaces. A library can be defined as Interface definition language (IDL);

287-662: A stable application binary interface (ABI) that is unaffected by compiler differences. This makes using COM advantageous for object-oriented C++ libraries that are to be used by clients compiled via different compilers. Introduced in 1987, Dynamic Data Exchange (DDE) was one of the first interprocess communication technologies in Windows . It allowed sending and receiving messages in so-called conversations between applications. Antony Williams, involved in architecting COM, distributed two papers within Microsoft that embraced

328-409: A subset of the whole COM interface. Over time, COM is being replaced with other technologies such as Microsoft .NET and web services (i.e. via WCF ). However, COM objects can be used in a .NET language via COM Interop . COM is similar to other component technologies such as SOM , CORBA and Enterprise JavaBeans , although each has its strengths and weaknesses. Unlike C++ , COM provides

369-766: Is Microsoft 's first server-side scripting language and engine for dynamic web pages . It was first released in December 1996, before being superseded in January 2002 by ASP.NET . Initially released as an add-on to Internet Information Services (IIS) via the Windows NT 4.0 Option Pack (1996), it is included as a component of Windows Server (since the initial release of Windows 2000 Server ). There have been three versions of ASP, each introduced with different versions of IIS: ASP 2.0 provides six built-in objects : Application, ASPError, Request, Response, Server, and Session. A Session object, for example, represents

410-408: Is a packaged extension in the form of a dynamic-link library (DLL) that allows objects to be graphically placed in a form and manipulated by properties and methods . These were later adapted for use by other languages such as Visual C++ . In 1992, with Windows 3.1 , Microsoft released OLE 2 with its new underlying object model , COM. The COM application binary interface (ABI) was the same as

451-548: 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. ASP.NET supports a number of programming models for building web applications: Other ASP.NET extensions include: On IIS  6.0 and lower, pages written using different versions of

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492-585: Is an unmanaged, native API. The API definitions are stored in ".winmd" files, which are encoded in ECMA 335 metadata format; the same CLI metadata format that .NET uses with a few modifications. This metadata format allows for significantly lower overhead than P/Invoke when WinRT is invoked from .NET applications. Nano-COM is a subset of COM focused on the application binary interface (ABI) aspects of COM that enable function and method calls across independently compiled modules/components. Nano-COM can be expressed in

533-446: Is currently in use as the base ABI technology for DirectX / Direct3D / DirectML . Since an ActiveX control (any COM component) runs as native code, with no sandboxing protection, there are few restrictions on what it can do. Using ActiveX components, as Internet Explorer supported, in a web page lead to problems with malware infections. Microsoft recognized the problem as far back as 1996 when Charles Fitzgerald said, "We never made

574-463: Is file based and multiple concurrent read and/or write requests will be blocked and processed in turn. Allows the management and fixing of non-fatal errors. Component Object Model Component Object Model ( COM ) is a binary-interface technology for software components from Microsoft that enables using objects in a language-neutral way between different programming languages , programming contexts, processes and machines . COM

615-418: Is the basis for other Microsoft domain specific component technologies including OLE , OLE Automation , ActiveX , COM+ , and DCOM as well as implementations such as DirectX , Windows shell , UMDF , Windows Runtime , and Browser Helper Object . COM enables object use with only knowing its interface; not its internal implementation. The component implementer defines interfaces that are separate from

656-467: The IUnknown interface, which exposes methods for reference counting and for accessing the other interfaces of the object – similar to type conversion , a.k.a. type casting. An interface is identified by an interface ID (IID), a GUID. A custom interface , anything derived from IUnknown , provides early bound access via a pointer to a virtual method table that contains a list of pointers to

697-612: The System.Transactions namespace provides the TransactionScope class, which provides transaction management without resorting to COM+. Similarly, queued components can be replaced by Windows Communication Foundation (WCF) with an MSMQ transport. There is limited support for backward compatibility. A COM object may be used in .NET by implementing a Runtime Callable Wrapper (RCW). NET objects that conform to certain interface restrictions may be used in COM objects by calling

738-695: The Windows Registry to call the MTS software, and not the component directly. Windows 2000 included Component Services control panel updates for configuring COM+ components. An advantage of COM+ was that it could be run in "component farms". Instances of a component, if coded properly, could be pooled and reused by new calls to its initializing routine without unloading it from memory. Components could also be distributed (called from another machine). COM+ and Microsoft Visual Studio provided tools to make it easy to generate client-side proxies, so although DCOM

779-470: The vtbls of the declared interfaces and a C file containing declarations of the interface GUIDs . C++ source code for a proxy module can also be generated by the MIDL compiler. This proxy contains method stubs for converting COM calls into remote procedure calls to enable DCOM for out-of-process communication. MIDL can generate a binary type library (TLB) that can be used by other tools to support access from other context. The following IDL code declares

820-500: 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. It is not essential to use the standard Web forms development model when developing with ASP.NET. Noteworthy frameworks designed for

861-574: The MAPI ABI (released in 1992), and like it was based on MSRPC and ultimately on the Open Group 's DCE/RPC . COM was created to replace DDE since its text-based conversation and Windows messaging design was not flexible enough to allow sharing application features in a robust and extensible way. In 1994, the OLE custom control (OCX) technology, based on COM, was introduced as the successor to VBX. At

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902-495: The Page class are MetaKeyword and MetaDescription. Parallel extensions and other .NET Framework 4.5 features The Mono Project supports "everything in .NET 4.7 except WPF , WWF , and with limited WCF and limited ASP.NET 4.7 async stack." ASP.NET can be run with Mono using one of three options: Apache hosting using the mod_mono module, FastCGI hosting, and XSP . Active Server Pages Active Server Pages ( ASP )

943-879: The Windows desktop, to activating objects running under different security contexts, and on different machines across the network. With this were added necessary features for configuring which users have authority to create, activate and call objects, for identifying the calling user, as well as specifying required encryption for security of calls. Microsoft introduced Microsoft Transaction Server (MTS) in Windows NT 4 in order to provide developers with support for distributed transactions , resource pooling, disconnected applications, event publication and subscription, better memory and processor (thread) management, as well as to position Windows as an alternative to other enterprise-level operating systems. Renamed to COM+ in Windows 2000,

984-524: The Windows scripting contexts. Component access is via interface methods . This allows for direct calling in-process and via the COM/DCOM sub-system access between processes and computers. A coclass , a COM class, implements one or more interfaces. It is identified by a class ID, called CLSID which is GUID , and by a human-readable programmatic identifier, called ProgID . A coclass is created via one of these identifiers. Each COM interface extends

1025-400: The allocator functions and restrict themselves to only use caller-allocated buffers. Nano-COM has no notion of classes, apartments, marshaling, registration, etc. Rather, object references are simply passed across function boundaries and allocated via standard language constructs (e.g., C++ new operator). The basis of Nano-COM was used by Mozilla to bootstrap Firefox (called XPCOM ), and

1066-685: The claim up front that ActiveX is intrinsically secure". Later versions of Internet Explorer prompt the user before installing an ActiveX control, allowing them to block installation. As a level of protection, an ActiveX control is signed with a digital signature to guarantee authenticity. It is also possible to disable ActiveX controls altogether, or to allow only a selected few. The transparent support for out-of-process COM servers promotes software safety in terms of process isolation . This can be useful for decoupling subsystems of large application into separate processes. Process isolation limits state corruption in one process from negatively affecting

1107-488: The concept of software components: Object Architecture: Dealing With the Unknown – or – Type Safety in a Dynamically Extensible Class Library in 1988 and On Inheritance: What It Means and How To Use It in 1990. These provided the foundation of many of the ideas behind COM. Object Linking and Embedding (OLE), Microsoft's first object-based framework, was built on DDE and designed specifically for compound documents . It

1148-477: The engine for better performance. ASP was supported until 14 January 2020 on Windows 7 . The use of ASP pages will be supported on Windows 8 for a minimum of 10 years from the Windows 8 release date. ASP is supported in all available versions of IIS as of 2024. ASP uses scripting on the server to generate content that is sent to the client's web browser via HTTP response. The ASP interpreter reads and executes all script code between <% and %> tags,

1189-429: The feature set was incorporated into the operating system as opposed to the series of external tools provided by MTS. At the same time, Microsoft de-emphasized DCOM as a separate entity. Components that used COM+ were handled more directly by the added layer of COM+; in particular by operating system support for interception. In the first release of MTS, interception was tacked on – installing an MTS component would modify

1230-426: The functions that implement the functions declared in the interface, in the order they are declared. An in-process invocation overhead is, therefore, comparable to a C++ virtual method call. Dispatching, a.k.a. late bound access, is provided by implementing IDispatch . Dispatching allows access from a wider range of programming contexts than a custom interface. Like many object-oriented languages, COM provides

1271-621: The implementation. Support for multiple programming contexts is handled by relying on the object for aspects that would be challenging to implement as a facility. Supporting multiple uses of an object is handled by requiring each object to destroy itself via reference-counting . Access to an object's interfaces (similar to Type conversion ) is provided by each object as well. COM is available only in Microsoft Windows and Apple's Core Foundation 1.3 and later plug-in application programming interface (API). The latter only implements

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1312-461: The integrity of the other processes, since they only communicate through strictly defined interfaces. Thus, only the affected subsystem needs to be restarted in order to regain valid state. This is not the case for subsystems within the same process, where a rogue pointer in one subsystem can randomly corrupt other subsystems. COM is supported via bindings in several languages, such as C , C++ , Visual Basic , Delphi , Python and several of

1353-415: The network with DCOM . The COM IDL is based on the feature-rich DCE/RPC IDL, with object-oriented extensions. Microsoft's implementation of DCE/RPC, MSRPC , is used as the primary inter-process communication mechanism for Windows NT services and internal components, making it an obvious choice of foundation. DCOM extends COM from merely supporting a single user with separate applications communicating on

1394-456: The original technology. Sun Java System ASP (formerly ChiliSoft ASP) was a popular and reportedly complete emulator, but it has been discontinued. The server object allows connections to databases (ADO), filesystem, and use of components installed on the server. This object stores global variables, which are variables accessible to all users. Stores variables accessible only to a single visitor, which are local variables. The session object

1435-421: The platform include: ASP.NET's release history tightly correlates with the .NET Framework releases: released together with Visual Studio .NET released together with Visual Studio .NET 2003 codename Whidbey released together with Visual Studio 2005 and Visual Web Developer Express and SQL Server 2005 Parallel extensions and other .NET Framework 4 features The two new properties added in

1476-415: The publisher or subscriber and the event system. .NET is Microsoft's component technology that supersedes COM. .NET hides many details of component creation and therefore eases development. .NET provides wrappers to commonly used COM controls. .NET can leverage COM+ via the System.EnterpriseServices namespace, and several of the services that COM+ provides have been duplicated in .NET. For example,

1517-406: The result of which is content generation. These scripts were written using VBScript , JScript , or PerlScript . The @Language directive, the <script language=" language " runat="server" /> syntax or server configuration can be used to select the language. In the example below, Response.Write Now() is in an HTML page; it would be dynamically replaced by the current time of

1558-555: The same time, Microsoft stated that OLE 2 would be known simply as "OLE". In early 1996, Microsoft found a new use for OCX – extending their web browser's capability. Microsoft renamed some parts of OLE relating to the Internet as ActiveX , and gradually renamed all OLE technologies to ActiveX, except the compound document technology that was used in Microsoft Office . Later in 1996, Microsoft extended COM to work across

1599-401: The server. Web pages with the .asp filename extension use ASP, although some web sites disguise their choice of scripting language for security purposes by using the more common .htm or .html extensions. Pages with the .aspx extension use compiled ASP.NET ; however, ASP.NET pages may still include some ASP scripting. The introduction of ASP.NET led to use of the term Classic ASP for

1640-584: Was introduced with Word and Excel in 1991, and was later included with Windows, starting with version 3.1 in 1992. An example of a compound document is a spreadsheet embedded in a Word document. As changes are made to the spreadsheet in Excel, they appear automatically in the Word document. In 1991, Microsoft introduced the Visual Basic Extension (VBX) technology with Visual Basic 1.0. A VBX

1681-476: Was used to make the remote call, it was easy to do for developers. COM+ also introduced a subscriber/publisher event mechanism called COM+ Events , and provided a new way of leveraging MSMQ (a technology that provides inter-application asynchronous messaging) with components called Queued Components . COM+ events extend the COM+ programming model to support late-bound (see Late binding ) events or method calls between

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