Asp.net 介绍

asp.net 介绍

　　

　　现在的ASP 应用程序中，不管你把它们写成什么样，总是要写长长短短的代码。然而ASP.NET的代码不仅容易编写，而且干净整洁，比ASP代码更便于阅读。同时，ASP.NET代码的构造方式提高了再利用性和共享性。ASP.NET 改进了配置、伸缩性、安全性和可靠性。对于简单的ASP应用程序，配置也简单，但是当你移到一个利用的组件的N层结构中时就会遇到问题。当你对这些程序进行配置以及维护时，DLL就会遇到陷阱问题（组件注册、版本、锁定的DLL等等）。ASP.NET中就取消了组件注册以及DLL锁定，更全面使用起XML配置的文件，所以解决了这个问题。这样你只需要执行复制文件的工作就能配置一个Web应用程序。ASP.NET对各种不同的浏览器提供了更加好的支持。对于ASP开发人员来说，浏览器兼容问题好像是一个没有办法解决的问题。无线应用程序协议WAP设备的引入还加深这个问题。本文中Web表单这部分描述了asp.NET是如何解决浏览器兼容性问题的。

　　（一）ADO.NET

　　在ASP.NET中的ADO.net和在asp中的ADO是相对应，它是ADO的改进版本。在ADO.NET中，通过Managed Provider所提供的应用程序编程接口(API)，可以轻松地访问各种数据源的数据，包括OLEDB支持的和ODBC支持的数据库。下面介绍ADO.NET中最重要的两个概念：Managed Provider和DataSet。

　　Managed Provider

　　在过去，通过ADO的数据存取采用了两层的基于连接的编程的模型。随着多层应用的不断需求，程序员需要一个无连接的模型。ADO.NET就产生了。ADO.NET的Managed Provider就是一个多层结构的无连接的一致的编程模型。Managed Provider提供了DataSet和数据中心（如MS SQL）之间的联系。Managed Provider包含了存取数据中心（数据库）的一系列的接口。主要有三个部分：

　　1、连接对象Connection、命令对象Command、参数对象Parameter提供了数据源和DataSet之间的接口。DataSetCommand接口定义了数据列和表映射，并最终取回一个DataSet。

　　 2、数据流提供了高性能的、前向的数据存取机制。通过IdataReader，你可以轻松而且高效率地访问数据流。







外文原文（复印件）

asp.Net introduced

　　In present ASP application procedure, no matter you wrote them any type, always must write the uneven code. However ASP.NET code is easy to compile, moreover clean is neat, is advantageous for compared to the ASP code reading. At the same time, ASP.NET code structure way enhanced the again use and sharing. ASP.NET improved the disposition, the elasticity, the security and the reliability. Regarding the simple ASP application procedure, the disposition is also simple, but when you transfer to uses the module in N structure can meet the question. When you carry on the disposition and the maintenance to these application procedures, DLL can meet the trap question (module registration, edition, fixed DLL and so on). ASP.NET then has cancelled the module registration as well as the DLL locking, comprehensively has used the XML disposition document, and thus has solved this problem. Like this you only need to carry out the duplication document work to be able to dispose a Web application procedure. ASP.NET has provided a better support to each kind of different browser. As for the ASP development personnel that, the browser compatible question resembles is a question which is unable to solve. The wireless application procedure agreement WAP equipment introduction also can deepen this question. In this article Web form this part described asp. How does NET solve the browser compatible problem.

　　(1) ADO.NET

　　ADO.Net in ASP.NET and is corresponds ADO in asp; it is the ADO improvement edition. In ADO.NET, the application procedure programming connection that provides through Managed Provider (API), may with ease visit each kind of data pool the data, including OLEDB support and ODBC support database. Under introduces ADO.INET most important two concepts: Managed Provider and DataSet.