计算机外文翻译---netframework概述(编辑修改稿)

计算机外文翻译---netframework概述(编辑修改稿)内容摘要：

that does not target the runtime is known as unmanaged code. The class library, the other main ponent of the .NET Framework, is a prehensive, objectoriented collection of reusable types that you can use to develop applications ranging from traditional mandline or graphical user interface (GUI) applications to applications based on the latest innovations provided by , such as Web Forms and XML Web services. The .NET Framework can be hosted by unmanaged ponents that load the mon language runtime into their processes and initiate the execution of managed code, thereby creating a software environment that can exploit both managed and unmanaged features. The .NET Framework not only provides several runtime hosts, but also supports the development of thirdparty runtime hosts. For example, hosts the runtime to provide a scalable, serverside environment for managed code. works directly with the runtime to enable applications and XML Web services, both of which are discussed later in this topic. Inter Explorer is an example of an unmanaged application that hosts the runtime (in the form of a MIME type extension). Using Inter Explorer to host the runtime enables you to embed managed ponents or Windows Forms controls in HTML documents. Hosting the runtime in this way makes managed mobile code (similar to Microsoft174。 ActiveX174。 controls) possible, but with significant improvements that only managed code can offer, such as semitrusted execution and isolated file storage. The following illustration shows the relationship of the mon language runtime and the class library to your applications and to the overall system. The illustration also shows how managed code operates within a larger architecture. Features of the Common Language Runtime The mon language runtime manages memory, thread execution, code execution, code safety verification, pilation, and other system services. These features are intrinsic to the managed code that runs on the mon language runtime. With regards to security, managed ponents are awarded varying degrees of trust, depending on a number of factors that include their origin (such as the Inter, enterprise work, or local puter). This means that a managed ponent might or might not be able to perform fileaccess operations, registryaccess operations, or other sensitive functions, even if it is being used in the same active application. The runtime enforces code access security. For example, users can trust that an executable embedded in a Web page can play an animation on screen or sing a song, but cannot access their personal data, file system, or work. The security features of the runtime thus enable legitimate Interdeployed software to be exceptionally feature rich. The runtime also enforces code robustness by implementing a strict typeandcodeverification infrastructure called the mon type system (CTS). The CTS ensures that all managed code is selfdescribing. The various Microsoft and thirdparty language pilers generate managed code that conforms to the CTS. This means that managed code can consume other managed types and instances, while strictly enforcing type fidelity and type safety. In addition, the managed environment of the runtime eliminates many mon software issues. For example, the runtime automatically handles object layout and manages references to objects, releasing them when they are no longer being used. This automatic memory management resolves the two most mon application errors, memory leaks and invalid memory references. The runtime also accelerates developer productivity. For example, programmers can write applications in their development language of choice, yet take full advantage of the runtime, the class library, and ponents written in other languages by other developers. Any piler vendor who chooses to target the runtime can do so. Language pilers that target the .NET Framework make the features of the .NET Framework available to existing code written in that language, greatly easing the migration process for existing applications. While the runtime is designed for the software of the future, it also supports software of today and yesterday. Interoperability between managed and unmanaged code enables developers to continue to use necessary COM ponents and DLLs. The runtime is designed to enhance performance. Although the mon language runtime provides many standard runtime services, managed code is never interpreted. A feature called justintime (JIT) piling enables all managed code to run in the native machine language of the system on which it is executing. Meanwhile, the memory manager removes the possibilities of fragmented memory and increases memory localityofreference to further increase performance. Finally, the runtime can be hosted by highperformance, serverside applications, such as Microsoft174。 SQL Server™ and Inter Information Services (IIS). This infrastructure enables you to use managed code to write your business logic, while still enjoying the superior performance of the industry39。 s best enterprise servers that support runtime hosting. Overview of provides consistent access to data sources such as Microsoft SQL Server, as well as data sources exposed through OLE DB and XML. Datasharing consumer applications can use to connect to these data sources and retrieve, manipulate, and update data. cleanly factors data access from data manipulation into discrete ponents that can be used separately or in tandem. includes .NET Framework data providers for connecting to a database, executing mands, and retrieving results. Those results are either processed directly, or placed in an DataSet object in order to be exposed to the user in an adhoc manner, bined with data from multiple sources, or remoted between tiers. The DataSet object can also be used in。