【導(dǎo)讀】.NETFramework旨在實(shí)現(xiàn)下列目標(biāo)：。提供一個(gè)一致的面向?qū)ο蟮木幊汰h(huán)境，而無論對(duì)象代碼是在本地存儲(chǔ)和。執(zhí)行，還是在本地執(zhí)行但在Inter上分布，或者是在遠(yuǎn)程執(zhí)行的。提供一個(gè)將軟件部署和版本控制沖突最小化的代碼執(zhí)行環(huán)境。提供一個(gè)可提高代碼（包括由未知的或不完全受信任的第三方創(chuàng)建的代。使開發(fā)人員的經(jīng)驗(yàn)在面對(duì)類型大不相同的應(yīng)用程序（如基于Windows的。應(yīng)用程序和基于Web的應(yīng)用程序）時(shí)保持一致。按照工業(yè)標(biāo)準(zhǔn)生成所有通信，以確保基于.NETFramework的代碼可與。事實(shí)上，代碼管理的概念是運(yùn)行庫的基本原則。托管代碼，而不以運(yùn)行庫為目標(biāo)的代碼稱為非托管代碼。題稍后將對(duì)這兩者進(jìn)行討論）?？稍趪?yán)格實(shí)施類型保真和類型安全的同時(shí)使用其他托管類型和實(shí)例。Framework的功能，這大大減輕了現(xiàn)有應(yīng)用程序的遷移過程的工作負(fù)擔(dān)。與.NETFramework中XML類的設(shè)計(jì)是并進(jìn)的，它們都是同一個(gè)結(jié)構(gòu)的組件。和.NETFramework中的XML類集中于DataSet對(duì)象。的XML，并且將其架構(gòu)包含為XML架構(gòu)定義語言架構(gòu)。

　　

【正文】 Using a .NET Framework data provider, you can execute stored procedures or data definition language (DDL) statements (for example, CREATE TABLE and ALTER COLUMN) to perform schema manipulation on a database or catalog. These mands do not return rows as a query would, so the Command object provides an ExecuteNonQuery method to process them. In addition to using ExecuteNonQuery to modify schema, you can also use this method to process SQL statements that modify data but that do not return rows, such as INSERT, UPDATE, and DELETE. Although rows are not returned by the ExecuteNonQuery method, input and output parameters and return values can be passed and returned via the Parameters collection of the Command object. Introduction to is more than the next version of Active Server Pages (ASP)。 it provides a unified Web development model that includes the services necessary for developers to build enterpriseclass Web applications. While is largely syntax patible with ASP, it also provides a new programming model and infrastructure for more scalable and stable applications that help provide greater protection. You can feel free to augment your existing ASP applications by incrementally adding functionality to them. is a piled, .NETbased environment。 you can author applications in any .NET patible language, including Visual Basic .NET, C, and JScript .NET. Additionally, the entire .NET Framework is available to any application. Developers can easily access the benefits of these technologies, which include the managed mon language runtime environment, type safety, inheritance, and so on. has been designed to work seamlessly with WYSIWYG HTML editors and other programming tools, including Microsoft Visual Studio .NET. Not only does this make Web development easier, but it also provides all the benefits that these tools have to offer, including a GUI that developers can use to drop server controls onto a Web page and fully integrated debugging support. Developers can use Web Forms or XML Web services when creating an application, or bine these in any way they see fit. Each is supported by the same infrastructure that allows you to use authentication schemes, cache frequently used data, or customize your application39。s configuration, to name only a few possibilities. ? Web Forms allow you to build powerful formsbased Web pages. When building these pages, you can use server controls to create mon UI elements, and program them for mon tasks. These controls allow you to rapidly build a Web Form out of reusable builtin or custom ponents, simplifying the code of a page. ? An XML Web service provides the means to access server functionality remotely. Using XML Web services, businesses can expose programmatic interfaces to their data or business logic, which in turn can be obtained and manipulated by client and server applications. XML Web services enable the exchange of data in clientserver or serverserver scenarios, using standards like HTTP and XML messaging to move data across firewalls. XML Web services are not tied to a particular ponent technology or objectcalling convention. As a result, programs written in any language, using any ponent model, and running on any operating system can access XML Web services. ? Each of these models can take full advantage of all features, as well as the power of the .NET Framework and .NET Framework mon language runtime. These features and how you can use them are outlined as follows: ? If you have ASP development skills, the new programming model will seem very familiar to you. However, the object model has changed significantly from ASP, making it more structured and objectoriented. Unfortunately this means that is not fully backward patible。 almost all existing ASP pages will have to be modified to some extent in order to run under . In addition, major changes to Visual Basic .NET mean that existing ASP pages written with Visual Basic Scripting Edition typically will not port directly to . In most cases, though, the necessary changes will involve only a few lines of code. ? Accessing databases from applications is an oftenused technique for displaying data to Web site visitors. makes it easier than ever to access databases for this purpose. It also allows you to manage the database from your code. ? provides a simple model that enables Web developers to write logic that runs at the application level. Developers can write this code in the text file or in a piled class deployed as an assembly. This logic can include applicationlevel events, but developers can easily extend this model to suit the needs of their Web application. ? provides easytouse application and sessionstate facilities that are familiar to ASP developers and are readily patible with all other .NET Framework APIs. ? For advanced developers who want to use APIs as powerful as the ISAPI programming interfaces that were included with previous versions of ASP, offers the IHttpHandler and IHttpModule interfaces. Implementing the IHttpHandler interface gives you a means of interacting with the lowlevel request and response services of the IIS Web server and provides functionality much like ISAPI extensions, but with a simpler programming model. Implementing the IHttpModule interface allows you to include custom events that participate in every request made to your application. ? takes advantage of performance enhancements found in the .NET Framework and mon language runtime. Additionally, it has been designed to offer significant performance improvements over ASP and other Web development platforms. All code is piled, rather than interpreted, which allows early binding, strong typing, and justintime (JIT) pilation to native code, to name only a few of its benefits. is also easily factora