The Model-View-Controller (MVC) architectural pattern separates an application into three main components: the model, the view, and the controller. The ASP.NET MVC framework provides an alternative to the ASP.NET Web Forms pattern for creating MVC-based Web applications. The ASP.NET MVC framework is a lightweight, highly testable presentation framework that (as with Web Forms-based applications) is integrated with existing ASP.NET features, such as master pages and membership-based authentication. The MVC framework is defined in the System.Web.Mvc namespace and is a fundamental, supported part of the System.Web namespace. MVC is a standard design pattern that many developers are familiar with. Some types of Web applications will benefit from the MVC framework. Others will continue to use the traditional ASP.NET application pattern that is based on Web Forms and postbacks. Other types of Web applications will combine the two approaches; neither approach excludes the other. MVC架构模式将应用程序分为模型-视图-控制器三个主要组织部分，ASP.NET MVC框架提供一种可以代替ASP.NET Web Forms模式来创建基于MVC的应用程序，ASP.NET MVC是轻量级的，高可测试的框架，并且可以结合现有的ASP.NET的特性如母板、基于membership的身份验证，MVC框架基础定义在System.Web.Mvc命名空间中的，成为System.Web命名空间的一部分。 MVC作为一个标准的设计模式被广大的开发人员所熟知。某些类型的Web应用程序将受益于MVC framework。其它类型的应用程序可以继续使用传统的基于Postbacks的Web forms模式进行ASP.NET开发，也可以结合这两种模式，它们是并行存在而不是互相冲突的。 The MVC framework includes the following components: MVC框架包含如下组成部分： Models. Model objects are the parts of the application that implement the logic for the application's data domain. Often, model objects retrieve and store model state in a database. For example, a Product object might retrieve information from a database, operate on it, and then write updated information back to a Products table in SQL Server. In small applications, the mo
在web config中 作如下配置：
<connectionStrings>
<add name="ydycon" connectionString="Provider=Microsoft.Jet.OLEDB.4.0;
Data Source=|DataDirectory|ydy.mdb" providerName="System.Data.OleDb"/>
</connectionStrings>
在.net文件中应用链接 ......
在ASP.NET网站开发中可能会遇到要更换数据库，如将Aceess换为SQL Server ，由于Aceess引用System.Data.OleDb命名空间，SQL Server引用System.Data.SqlClient命名空间。在一般程序代码中我们需要更改连接字符串，ADO.NET数据访问命令对象，最麻烦的是不同数据库有各自不同Sql命令。我们可以使用抽象工厂模式实现ASP.NET访问� ......
