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51-476: C++/CLI should be thought of as a language of its own (with a new set of keywords, for example), instead of the C++ superset-oriented Managed C++ (MC++) (whose non-standard keywords were styled like __gc or __value ). Because of this, there are some major syntactic changes, especially related to the elimination of ambiguous identifiers and the addition of .NET-specific features. Many conflicting syntaxes, such as

102-516: A Windows domain , or equipped with a special activation key obtained from Microsoft. However these restrictions were lifted in the Windows November 10 Update, where users can freely sideload any app signed with a trusted certificate by enabling a setting. In a major departure from Win32 and similarly to .NET Framework 4.5 , most APIs which are expected to take significant time to complete are implemented as asynchronous . When calling

153-636: A language binding is termed a language projection. Standard C++ is a first-class citizen of the WinRT platform. As of Windows 10, version 1803, the Windows SDK contains C++/WinRT. C++/WinRT is an entirely standard modern C++17 language projection for Windows Runtime (WinRT) APIs, implemented as a header-file-based library, and designed to provide first-class access to the modern Windows API. With C++/WinRT, Windows Runtime APIs can be authored and consumed using any standards-compliant C++17 compiler. WinRT

204-642: A Microsoft effort to reconcile traditional Windows desktop and the UWP app model. With the introduction of the Universal Windows Platform (UWP), the platform has received many API bridges that allow programs originally developed for other platforms to be ported easily while taking advantage of UWP features. Microsoft has provided bridges for Android (defunct since 2016), iOS ( Cocoa Touch ), Progressive Web Apps , Silverlight , as well as traditional Windows desktop apps (using MSIX packaging from

255-514: A WinRT app in JavaScript, its features are adapted to follow JavaScript naming conventions, and namespaces are also mapped to JavaScript objects. Microsoft is in the process of projecting WinRT APIs to languages other than C++. One example is Rust/WinRT, an interface for programs written in Rust to consume and author WinRT APIs. Rust/WinRT is part of Windows App SDK (formerly Project Reunion),

306-617: A Windows Runtime asynchronous function, the task is started on another thread or process and the function returns immediately, freeing the app to perform other tasks while waiting for results. The asynchronous model requires new programming language constructs. Each language provides their own way to consume asynchronous APIs. Parts of the built-in API needing asynchronous access include on-screen messages and dialogs, file access, Internet connectivity, sockets, streams, devices and services, and calendar, contacts and appointments. The metadata describes

357-456: A ^, every & becomes an %, but the rest of the syntax is unchanged, except for an important addition: for .NET classes, operator overloading is possible not only for classes themselves, but also for references to those classes. This feature is necessary to give a ref class the semantics for operator overloading expected from .NET ref classes. (In reverse, this also means that for .NET framework ref classes, reference operator overloading often

408-558: A full-blown runtime, such as type activation. That is, WinRT is an "API delivery system". Apps using the Windows Runtime may run inside a sandboxed environment to allow greater security and stability and can natively support both x86 and ARM . WinRT components are designed with interoperability among multiple languages and APIs in mind, including native, managed and scripting languages. Built-in APIs provided by Windows which use

459-400: A native and consistent experience regardless of the programming language. Since Windows Runtime is projected to various languages, some restrictions on fundamental data types exist so as to host all such languages. Programmers must be careful with the behavior of those types when used with public access (for method parameters, method return values, properties, etc.). Windows Phone 8.1 uses

510-697: A sandbox and need explicit user approval to access critical OS features and underlying hardware. By default, file access is restricted to several predetermined locations, such as the directories Documents or Pictures. WinRT applications are packaged in the .appx and later the .msix file format ; based upon Open Packaging Conventions , it uses a ZIP format with added XML files. WinRT applications are distributed mostly through an application store named Microsoft Store , where Windows apps (termed Windows Store apps ) can be purchased and downloaded by users. Initially, WinRT apps could only be sideloaded from outside Windows Store on Windows 8 or RT systems that are part of

561-667: A set of built-in APIs which are built on the WinRT ABI which provide everything from the XAML-based WinUI library and device access such as camera, microphone etc... The previous C++/CX (Component Extensions) language, which borrows some C++/CLI syntax, was introduced for writing and consuming WinRT components with less glue code visible to the programmer, relative to classic COM programming in C++, and imposes fewer restrictions relative to C++/CLI on mixing types. The Component Extensions of C++/CX are recommended for use at

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612-560: A simple DLL file. Notes: The following contains main points and programmatic standards that differ between Managed C++ and other well known programming languages that are similar in concept. Disadvantages Advantages Differences Disadvantages Advantages Differences Disadvantages Advantages WinRT Windows Runtime ( WinRT ) is a platform-agnostic component and application architecture first introduced in Windows 8 and Windows Server 2012 in 2012. It

663-650: A version of the Windows Runtime named the Windows Phone Runtime . It enables developing applications in C# and VB.NET, and Windows Runtime components in C++/CX. Although WP8 brought limited support, the platform did eventually converge with Windows 8.1 in Windows Phone 8.1 . Windows Phone 8 has limited support for developing and consuming Windows Runtime components through Windows Phone Runtime . Many of

714-554: Is impossible in C++/CX. Development using either HTML5 or WinJS is unsupported on Windows Phone 8. Windows Runtime support on Windows Phone 8.1 converges with Windows 8.1. The release brings a full Windows Runtime API to the platform, including support for WinRT XAML , and language bindings for C++/CX , and HTML5 - JavaScript . There is also a project type called Universal apps to enable apps to share code across 8.1 versions of Windows Phone and Windows. The Windows Phone 8 Silverlight Framework has been updated. It can exploit some of

765-482: Is a handle of a passed-by-reference variable. It is similar in concept to using *& (reference to a pointer) in standard C++, and (in function declarations) corresponds to the ref keyword applied to types in C#, or ByRef in Visual Basic .NET . C++/CLI uses a ^% syntax to indicate a tracking reference to a handle. The following code shows an example of the use of tracking references. Replacing

816-456: Is a native platform and supports any native (and standard) C++ code, so that a C++ developer can reuse existing native C/C++ libraries. With C++/WinRT, there are no language extensions. There are two other legacy options for using WinRT from C++: Windows Runtime C++ Template Library (WRL), an ATL -style template library (similar to Windows Template Library or WTL), and C++/CX (C++ with Component Extensions) which resembles C++/CLI. Because of

867-511: Is implemented in C++ and officially supports development in C++ (via C++/WinRT , C++/CX or WRL), Rust/WinRT , Python/WinRT , JavaScript - TypeScript , and the managed code languages C# and Visual Basic (.NET) (VB.NET). WinRT is not a runtime in a traditional sense but rather a language-independent application binary interface based on COM to allow object-oriented APIs to be consumed from multiple languages, with services usually provided by

918-509: Is implicitly implemented in C++/CLI.) For example, comparing two distinct String references (String^) via the operator == will give true whenever the two strings are equal. The operator overloading is static, however. Thus, casting to Object^ will remove the overloading semantics. C++/CLI allows C++ programs to consume C# programs in C# DLLs. Here the #using keyword shows the compiler where

969-516: Is most likely the preferred option. Managed C++ is geared towards object-oriented programming. A major difference between standard C++ and Managed C++ is that multiple inheritance is not supported, and a class managed under the CLR's garbage collector cannot inherit more than one class. This is because of a limitation of the CLR. Key features: The following examples depict the use of Managed C++ as compared to standard C++: A new preprocessor directive

1020-417: Is no need to call the delete operator. To achieve the same with unmanaged code, the delete keyword is required: Notes: the public keyword to modify the access of the a __gc designated class. A __gc designated class can be destroyed manually using the delete keyword, but only if the __gc designated class has a user-defined destructor. The preceding code must be compiled with /clr and /LD to produce

1071-507: Is often used as a "bridge". Programs coded in Managed C++ provide additional functionality of the .NET Framework and the CLR . Most notable of these is garbage collection , which relieves the programmer of manual memory management. The garbage collector (GC) is handled by the CLR. Memory management is executed quite quickly, but for more performance critical applications, native, unmanaged code

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1122-484: Is required. In addition to that, more #using directives are required to import more libraries to use more namespaces in the Base Class Library, such as and to use Windows Forms. /clr enables any code referencing the .NET Framework to be compiled as CIL . The preceding code can be compiled and executed without any fear of memory leaks . Because class gc is managed under the garbage collector, there

1173-403: Is run as a part of the garbage collection routine . The C++ destructor syntax ~ ClassName () also exists for managed objects, and better reflects the "traditional" C++ semantics of deterministic destruction (that is, destructors that can be called by user code with delete ). In the raw .NET paradigm, the nondeterministic destruction model overrides the protected Finalize method of

1224-463: Is stored in a separate metadata file that can be reflected like ordinary CLI assemblies . Since it is the same format as CLI metadata, WinRT APIs can be used from managed CLI languages as if it was just a .NET API. WinRT has a rich object-oriented class -based type system that is built on the metadata. It supports constructs with corresponding constructs in the .NET framework: classes , methods , properties , delegates , and events . One of

1275-418: Is the metadata. This metadata makes it possible to interface with the component from any other WinRT language. The runtime requires WinRT components that are built with .NET Framework to use the defined interface types or .NET type interfaces, which automatically map to the first named. Inheritance is as yet not supported in managed WinRT components, except for XAML classes. Programs and libraries targeted for

1326-509: The CLR such as C# and Visual Basic .NET as well as make use of features provided by the CLR such as garbage collection . This means Managed C++ occupies a unique position in the gallery of .NET languages. It is the only language that can communicate directly with .NET languages (such as C#, VB.NET) as well as native C++. The other .NET languages can only communicate with C++ code via PInvoke or COM . But since Managed C++ can communicate directly in both managed and standard C++ contexts, it

1377-612: The Windows App SDK ). WinRT comes with an application programming interface (API) in the form of a class library that exposes the features of Windows 8 for the developer, like its immersive interface API. It is accessible and consumable from any supported language. The Windows Runtime classes is a set SDKs that provide access to all functionality from the XAML parser to the camera function. The SDKs are implemented as native C/C++ libraries (unmanaged). The naming conventions for

1428-549: The API definitions are stored in .winmd files, which are encoded in ECMA 335 metadata format, which .NET Framework also uses with a few modifications. For WinRT components implemented in native code, the metadata file only contains the definition of methods, classes, interfaces and enumerations and the implementation is provided in a separate DLL. This common metadata format makes it easier to consume WinRT APIs from .NET apps with simpler syntax than P/Invoke . Windows provides

1479-617: The API-boundary only, not for other purposes. Regular C++ (with COM-specific discipline) can also be used to program with WinRT components, with the help of the Windows Runtime C++ Template Library (WRL), which is similar in purpose to what Active Template Library provides for COM. In 2019, Microsoft deprecated C++/CX in favor of the C++/WinRT header library. Most WinRT applications run within

1530-503: The APIs written using the WinRT ABI. It defines a programming model that makes it possible to write object-oriented code that can be shared across programming languages , and enables services like reflective programming (reflection). Herb Sutter , C++ expert at Microsoft , explained during his session on C++ at the 2011 Build conference that the WinRT metadata is in the same format as CLI metadata . Native code (i.e., processor-specific machine code) cannot contain metadata, so it

1581-678: The C++ syntax and language to the .NET Framework . These extensions were created by Microsoft to allow C++ code to be targeted to the Common Language Runtime (CLR) in the form of managed code , as well as continue to interoperate with native code. In 2004, the Managed C++ extensions were significantly revised to clarify and simplify syntax and expand functionality to include managed generics . These new extensions were designated C++/CLI and included in Microsoft Visual Studio 2005 . The term Managed C++ and

C++/CLI - Misplaced Pages Continue

1632-507: The DLL is located for its compilation metadata. This simple example requires no data marshalling . The C# source code content of MyCS.dll. This examples shows how strings are marshalled from C++ strings to strings callable from C# then back to C++ strings. String marshalling copies the string contents to forms usable in the different environments. The C# code is not in any way C++-aware. C++/C# interoperability allows C++ simplified access to

1683-520: The WinRT ABI are commonly known as WinRT APIs; however, anyone can use the WinRT ABI for their own APIs. WinRT is implemented in the programming language C++ and is object-oriented by design. Its underlying technology, the Windows API (Win32 API), is written mostly in the language C . It is an unmanaged application binary interface based on Component Object Model (COM) that allows interfacing from multiple languages, as does COM. However,

1734-401: The WinRT runtime can be created and consumed from several platforms and programming languages. Notably C / C++ (either with language extensions offering first-class support for WinRT concepts, or with a lower-level template library allowing to write code in standard C++), .NET ( C# and Visual Basic (.NET) (VB.NET)) and JavaScript . This is made possible by the metadata. In WinRT terminology,

1785-709: The Windows Runtime APIs in Windows 8 that handle core operating system functions have been ported to Windows Phone 8. Support for developing native games using C++/CX and DirectX has been added, by request from the game development industry. However, the Windows Phone XAML Framework is still based on the same Microsoft Silverlight framework, as in Windows Phone 7, for backward compatibility. Thus, as of 2016 , XAML development

1836-689: The XAML-based WinUI , and are primarily written in C#, VB.NET, and for the first time for XAML, with native code using C++/CX. Although not yet officially supported, programs can also be written in other .NET languages. With .NET 5, Microsoft removed the built-in WinRT support and instead created CsWinRT, a tool that generates interop code for accessing Windows Runtime APIs similar to how C++/WinRT works. Classes defined in WinRT components that are built in managed .NET languages must be declared as sealed , so they cannot be derived from. However, non-sealed WinRT classes defined elsewhere can be inherited from in .NET, their virtual methods overridden, and so on; but

1887-557: The complete class while allowing clean separation of the machine-generated and human-edited parts of a class implementation into different files. The .NET Framework and the Common Language Runtime (CLR) are integrated into the WinRT as a subplatform. It has influenced and set the standards for the ecosystem through the metadata format and libraries. The CLR provides services like JIT-compilation code and garbage collection . WinRT applications using .NET languages use

1938-403: The components (classes and other members) in the API are heavily influenced by the .NET naming conventions which uses camel case (specifically PascalCase). Microsoft recommends users to follow these rules in case where no others are given. These conventions are projected differently in some languages, like JavaScript, which converts it to its conventions and the other way around. This is to give

1989-449: The entire world of .NET features. C++/CX targeting WinRT , although it produces entirely unmanaged code, borrows the ref and ^ syntax for the reference-counted components of WinRT, which are similar to COM "objects". Managed Extensions for C%2B%2B Managed Extensions for C++ or Managed C++ is a deprecated set of language extensions for C++ , including grammatical and syntactic extensions, keywords and attributes, to bring

2040-536: The extensions it refers to are thus deprecated and superseded by the new extensions. Microsoft introduced Managed Extensions for C++ in Microsoft Visual C++ 2002 (MSVC++). Microsoft attempted to minimise the deviations between standard C++ and Managed Extensions for C++, resulting in core differences between the two being syntactically obscured. MSVC++ 2003 and 2005 also provided support for writing programs in Managed C++. In 2004, Managed Extensions for C++

2091-475: The inherited managed class must still be sealed. Members that interface with another language must have a signature with WinRT types or a managed type that is convertible to these. WinRT applications can also be coded using HTML with JavaScript in code-behind , which are run using the Trident rendering engine and Chakra JavaScript engine, both of which are also used by Internet Explorer . When coding

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2142-504: The internal consumption requirements at Microsoft, WRL is exception-free, meaning its return-value discipline is HRESULT -based just like that of COM. C++/CX on the other hand wraps-up calls to WinRT with code that does error checking and throws exceptions as appropriate. C++/CX has several extensions that enable integration with the platform and its type system. The syntax resembles the one of C++/CLI although it produces native (although not standard) code and metadata that integrates with

2193-616: The major additions to WinRT relative to COM is the cross- application binary interface (ABI), .NET-style generics . Only interfaces and delegates can be generic, runtime classes and methods in them can't. Generic interfaces are also known as parameterized interfaces. In C++/CX, they are declared using the keyword generic with a syntax very similar to that of keyword template . WinRT classes (ref classes) can also be genericized using C++ templates, but only template instantiations can be exported to .winmd metadata (with some name mangling ), unlike WinRT generics which preserve their genericity in

2244-473: The metadata. WinRT also provides a set of interfaces for generic containers that parallel those in the C++ Standard Library , and languages provide some reciprocal (back-and-forth) conversion functions. The consumption of WinRT collections in .NET languages (e.g., C# and VB) and in JavaScript is more transparent than in C++, with automated mappings into their natural equivalents occurring behind

2295-589: The multiple versions of operator new () in MC++, have been split: in C++/CLI, .NET reference types are created with the new keyword gcnew (i.e. garbage collected new()). Also, C++/CLI has introduced the concept of generics from .NET (similar, for the most common purposes, to standard C++ templates, but quite different in their implementation). In MC++, there were two different types of pointers : __nogc pointers were normal C++ pointers, while __gc pointers worked on .NET reference types. In C++/CLI, however,

2346-448: The only type of pointer is the normal C++ pointer, while the .NET reference types are accessed through a "handle", with the new syntax ClassName ^ (instead of ClassName * ). This new construct is especially helpful when managed and standard C++ code is mixed; it clarifies which objects are under .NET automatic garbage collection and which objects the programmer must remember to explicitly destroy. A tracking reference in C++/CLI

2397-534: The root Object class, while the deterministic model is implemented through the IDisposable interface method Dispose (which the C++/CLI compiler turns the destructor into). Objects from C# or VB.NET code that override the Dispose method can be disposed of manually in C++/CLI with delete just as .NET classes in C++/CLI can. Operator overloading works analogously to standard C++. Every * becomes

2448-610: The runtime. For example, WinRT objects may be allocated with ref new , which is the counterpart of gcnew from C++/CLI. The hat operator ^ retains its meaning, however in the case where both the caller and callee are written in C++ and living in the same process, a hat reference is simply a pointer to a vptr to a virtual method table (vtable, VMT). Along with C++/CX, relative to traditional C++ COM programming, are partial classes , again inspired by .NET. These allow instance WinRT XAML code to be translated into C++ code by tools, and then combined with human-written code to produce

2499-457: The scenes. When authoring a WinRT component in a managed language, some extra, COM-style rules must be followed, e.g. .NET framework collection types cannot be declared as return types, but only the WinRT interfaces that they implement can be used at the component boundary. Classes that are compiled to target the WinRT are called WinRT components . They are classes that can be written in any supported language and for any supported platform. The key

2550-402: The tracking reference with a regular handle variable would leave the resulting string array with 10 uninitialized string handles, as only copies of the string handles in the array would be set, due to them being passed by value rather than by reference. Another change in C++/CLI is the introduction of the finalizer syntax ! ClassName () , a special type of nondeterministic destructor that

2601-707: Was deprecated in favor of C++/CLI , a second attempt by Microsoft at supporting programming for the Common Language Infrastructure using C++. Managed refers to managed code that it is run in, or managed by, the .NET virtual machine that functions as a sandbox for enhanced security in the form of more runtime checks, such as buffer overrun checks. Additionally, applications written in Managed C++ compile to CIL —Common Intermediate Language—and not directly to native CPU instructions like standard C++ applications do. Managed C++ code could inter-operate with any other language also targeted for

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