【正文】
Framework, which promised to address the old problems and meet the goals for the nextgeneration system. The .NET Framework is a much more consistent and objectoriented environment than either the MFC or COM programming technologies. Some of its features include the following: ? Multiple platforms: The system runs on a broad range of puters, from servers and desktop machines to PDAs and cell phones. ? Industry standards: The system uses industry standard munication protocols, such as XML, HTTP, SOAP, and WSDL. ? Security: The system can provide a much safer execution environment, even in the presence of code obtained from suspect sources. The .NET Framework is made up of three ponents. The execution environment is called the Common Language Runtime (CLR). The CLR manages program execution at run time, including the following: ? Memory management ? Code safety verification ? Code execution ? Garbage collection The programming tools include everything you need for coding and debugging, including the following: ? The Visual Studio integrated development environment ? .NETpliant pilers (., C, VB, JScript, and managed C++) ? Debuggers ? Serverside improvements, such as The Base Class Library (BCL) is a large class library used by the .NET Framework and available for you to use in your programs as well. The .NET Framework offers programmers considerable improvements over previous Windows programming environments. A brief overview of its features and their benefits is given in the following sections. ObjectOriented Development Environment The CLR, the BCL, and C are designed to be thoroughly objectoriented and act as a wellintegrated environment. The system provides a consistent, objectoriented model of programming for both local programs and distributed systems. It also provides a software development interface for desktop application programming, mobile application programming, and web development, consistent across a broad range of targets, from servers to cell phones. Automatic Garbage Collection The CLR has a service called the Garbage Collector (GC), which automatically manages memory for you. ? The GC automatically deletes objects from memory that your program will no longer access. ? The GC relieves the programmer of tasks that he or she has traditionally had to perform, such as