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<p class=1 style='margin-left:37.55pt;FTEL:-16.1pt'><span lang=EN-US>●<span
style='font:7.0pt "Times New Roman"'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span><span
lang=EN-US>WebForm1.aspx</span><span style='font-family:宋体;letter-spacing:-1.0pt'>——</span><span
style='letter-spacing:-1.0pt'> </span><span lang=EN-US>Web</span><span
style='font-family:宋体'>应用程序中的第一个</span><span lang=EN-US>ASP.NET</span><span
style='font-family:宋体'>页面</span></p>

<p class=MsoNormal><span style='font-family:宋体'>在本章和后面的两章中，将介绍所有生成的文件，现在则说明该应用程序的实质，即</span><span
lang=EN-US>VS.NET</span><span style='font-family:宋体'>生成的</span><span lang=EN-US>.aspx</span><span style='font-family:宋体'>文件。</span></p>

<p class=MsoNormal><a FTEL=aspx1><span style='font-family:宋体'>可以在设计视图或代码视图</span><span
lang=EN-US>(</span></a><span style='font-family:宋体'>以及设计器中的</span><span
lang=EN-US>HTML</span><span style='font-family:宋体'>视图</span><span lang=EN-US>)</span><span
style='font-family:宋体'>中查看</span><span lang=EN-US>.aspx</span><span
style='font-family:宋体'>文件。这与</span><span lang=EN-US>Windows </span><span
style='font-family:宋体'>窗体完全相同。</span><span lang=EN-US>VS.NET</span><span
style='font-family:宋体'>中的起始视图是设计视图，如图</span><span lang=EN-US>25-3</span><span
style='font-family:宋体'>所示。</span></p>

<p align=center><span lang=EN-US><img width=447 height=411
src="25/image004.jpg"></span></p>

<p align=center style='FTEL:8.15pt'><span style='font-family:宋体'>图</span><span
lang=EN-US>&nbsp; 25-3</span></p>

<p class=MsoNormal><span style='font-family:宋体;letter-spacing:-.1pt'>该视图中的文本在默认情况下不是我们在应用程序中看到的文本，而是</span><span
lang=EN-US style='letter-spacing:-.1pt'>VS.NET</span><span style='font-family:
宋体;letter-spacing:-.1pt'>中的一个注释，说明使用什么布局模式。这里使用</span><span lang=EN-US
style='letter-spacing:-.1pt'>GridLayout</span><span style='font-family:宋体;
letter-spacing:-.1pt'>模式，这样在控件的定位上就有很大的灵活性，如果需要传统的</span><span lang=EN-US
style='letter-spacing:-.1pt'>HTML</span><span style='font-family:宋体;letter-spacing:
-.1pt'>类型的定位模式，可以改为</span><span lang=EN-US style='letter-spacing:-.1pt'>FlowLayout
</span><span style='font-family:宋体;letter-spacing:-.1pt'>模式。</span></p>

<p class=MsoNormal style='FTEL:3.25pt'><span style='font-family:宋体'>如果从布局下面的按钮中选择</span><span
lang=EN-US>HTML</span><span style='font-family:宋体'>视图，则应在</span><span
lang=EN-US>.aspx</span><span style='font-family:宋体'>文件中生成如下代码：</span></p>

<p class=2 style='margin-top:8.15pt;margin-right:0cm;FTEL:0cm;
margin-left:21.45pt;FTEL:.0001pt;FTEL:18.45pt'><span
lang=EN-US>&lt;%@ Page language=&quot;c#&quot;
Codebehind=&quot;WebForm1.aspx.cs&quot; AutoEventWireup=&quot;false&quot;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Inherits=&quot;PCSWebApp1.WebForm1&quot; %&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&lt;!DOCTYPE
HTML PUBLIC &quot;-//W3C//DTD HTML 4.0 Transitional//EN&quot; &gt;</span></p>



<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&lt;html&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;
&lt;head&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&lt;title&gt;WebForm1&lt;/title&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&lt;meta FTEL=&quot;GENERATOR&quot; Content=&quot;Microsoft Visual Studio 7.1&quot;&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&lt;meta FTEL=&quot;CODE</span><span lang=EN-US style='font-family:"Baskerville BE Regular"'>_</span><span
lang=EN-US>LANGUAGE&quot; Content=&quot;C#&quot;&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&lt;meta FTEL=&quot;vs</span><span lang=EN-US style='font-family:"Baskerville BE Regular"'>_</span><span
lang=EN-US>defaultClientScript&quot; content=&quot;JavaScript&quot;&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&lt;meta FTEL=&quot;vs</span><span lang=EN-US style='font-family:"Baskerville BE Regular"'>_</span><span
lang=EN-US>targetSchema&quot;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
content=&quot;http://schemas.microsoft.com/intellisense/ie5&quot;&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;
&lt;/head&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;
&lt;body MS</span><span lang=EN-US style='font-family:"Baskerville BE Regular"'>_</span><span
lang=EN-US>POSITIONING=&quot;GridLayout&quot;&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&lt;form id=&quot;Form1&quot; method=&quot;post&quot;
Runat=&quot;server&quot;&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&lt;/form&gt;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&nbsp;&nbsp;
&lt;/body&gt;</span></p>

<p class=2 style='margin-top:0cm;margin-right:0cm;FTEL:8.15pt;
margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>&lt;/html&gt;</span></p>

<p class=MsoNormal><span style='font-family:宋体'>在</span><span lang=EN-US>&lt;html&gt;</span><span
style='font-family:宋体'>元素中，填充了一些与我们没有什么关系的元数据，</span><span lang=EN-US>&lt;form&gt;</span><span
style='font-family:宋体'>元素则包含了</span><span lang=EN-US>ASP.NET</span><span
style='font-family:宋体'>代码。这里最重要的属性是</span><span lang=EN-US>runat</span><span
style='font-family:宋体'>。与本节前面的服务器端代码块一样，这个属性设置为</span><span lang=EN-US>server</span><span
style='font-family:宋体'>，表示窗体的处理将在服务器上进行。如果没有包含这个属性，就不会在服务器端上完成任何处理，窗体也不会执行任何操作。在</span><span
lang=EN-US>ASP.NET</span><span style='font-family:宋体'>页面中，只有一个服务器端</span><span
lang=EN-US>&lt;form&gt;</span><span style='font-family:宋体'>元素。</span></p>

<p class=MsoNormal><span style='font-family:宋体'>这段代码中另一个比较重要的东西是顶部的</span><span
lang=EN-US>&lt;@% Page %&gt;</span><span style='font-family:宋体'>标记，它定义了对于</span><span
lang=EN-US>C# Web</span><span style='font-family:宋体'>应用程序开发人员来说非常重要的页面特性。首先，</span><span
lang=EN-US>language</span><span style='font-family:宋体'>属性指定在页面中使用</span><span
lang=EN-US>C#</span><span style='font-family:宋体'>语言，与前面的</span><span
lang=EN-US>&lt;script&gt;</span><span style='font-family:宋体'>块一样</span><span
lang=EN-US>(Web</span><span style='font-family:宋体'>应用程序默认的语言是</span><span
lang=EN-US>VB.NET</span><span style='font-family:宋体'>，使用</span><span
lang=EN-US>Web.config</span><span style='font-family:宋体'>配置文件可以修改这个属性</span><span
lang=EN-US>)</span><span style='font-family:宋体'>。下面三个属性都是必需的，因为驱动页面的代码由</span><span
lang=EN-US>VS.NET</span><span style='font-family:宋体'>设置，存放在一个单独的</span><span
lang=EN-US>WebForm1.aspx.cs</span><span style='font-family:宋体'>文件中，这个文件</span><span
lang=EN-US>(</span><span style='font-family:宋体'>详见后面的内容</span><span lang=EN-US>)</span><span
style='font-family:宋体'>包含一个类定义，这个类用作</span><span lang=EN-US>Web</span><span
style='font-family:宋体'>窗体页面的基类。现在开始介绍</span><span lang=EN-US>ASP.NET</span><span
style='font-family:宋体'>如何与对象模型连接起来。这个基类可以和该文件中的代码一起使用，生成显示给用户的</span><span
lang=EN-US>HTML</span><span style='font-family:宋体'>。</span></p>

<p class=a3 style='margin-top:8.15pt;FTEL:21.45pt'><span
style='font-family:黑体'>注意：</span></p>

<p class=a1 style='FTEL:8.15pt;FTEL:21.45pt'><span
style='font-family:楷体_GB2312'>并不是所有的</span><span lang=EN-US>.aspx</span><span
style='font-family:楷体_GB2312'>文件都需要这个多层模型，默认情况下</span><span lang=EN-US>.aspx</span><span
style='font-family:楷体_GB2312'>文件只需要使用基本的</span><span lang=EN-US>.NET Web</span><span
style='font-family:楷体_GB2312'>窗体类作为页面的基类。此时，</span><span lang=EN-US>.aspx</span><span
style='font-family:楷体_GB2312'>文件应包含</span><span lang=EN-US>&lt;script&gt;</span><span
style='font-family:楷体_GB2312'>中的所有</span><span lang=EN-US>C#</span><span
style='font-family:楷体_GB2312'>代码。</span></p>

<p class=MsoNormal><span style='font-family:宋体'>前面为页面提供了一个定制的基类，也可以提供定制的事件。为了确保</span><span
lang=EN-US>ASP.NET</span><span style='font-family:宋体'>引擎认可这些事件，需要使用</span><span
lang=EN-US>AutoEventWireup</span><span style='font-family:宋体'>属性，它表示</span><span
lang=EN-US>Page_Load()</span><span style='font-family:宋体'>事件处理程序</span><span
lang=EN-US>(</span><span style='font-family:宋体'>加载页面时调用</span><span lang=EN-US>)</span><span
style='font-family:宋体'>是否能自动连接</span><span lang=EN-US>OnPageLoad</span><span
style='font-family:宋体'>事件。把这个属性设置为</span><span lang=EN-US>false</span><span
style='font-family:宋体'>，就必须提供代码来链接该事件，但这样可以获得更大的灵活性。</span></p>

<p class=MsoNormal><span style='font-family:宋体'>下面看看为这个文件生成的后置代码。在</span><span
lang=EN-US>Solution Explorer</span><span style='font-family:宋体'>上右击</span><span
lang=EN-US>WebForm1.aspx</span><span style='font-family:宋体'>，选择</span><span
lang=EN-US>View Code</span><span style='font-family:宋体'>，把</span><span
lang=EN-US>WebForm1.aspx.cs</span><span style='font-family:宋体'>中的代码加载到文本编辑器中。在这段代码中，首先是所需要的默认命名空间引用集：</span></p>

<p class=2 style='margin-top:8.15pt;margin-right:0cm;FTEL:0cm;
margin-left:21.45pt;FTEL:.0001pt;FTEL:18.45pt'><span
lang=EN-US>using System;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>using
System.Collections;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>using
System.ComponentModel;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>using
System.Data;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>using
System.Drawing;</span></p>

<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>using
System.Web;</span></p>