100165699.htm
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HTM
750 行
FTEL="OLE_LINK2"></a><a FTEL="OLE_LINK4"></a><a FTEL="OLE_LINK1"><span
lang=EN-US><%@ Control Language="c#"
AutoEventWireup="false" Codebehind="PCSUserC1.ascx.cs"</span></a></p>
<p class=a6 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
Inherits="PCSUserCWebApp1.PCSUserC1"</span></p>
<p class=a6 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
TargetSchema="http://schemas.microsoft.com/intellisense/ie5"%></span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US><table
cellspacing=4></span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=DA>
<tr valign="middle"></span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=DA> </span><span
lang=EN-US> <td></span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
<asp:Image Runat="server" ID="suitPic"
ImageURL="club.bmp"/></span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
</td></span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
<td></span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
<asp:Label Runat="server"
ID="suitLabel">Club</asp:Label></span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
</td></span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
</tr></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></table></span></p>
<p class=MsoNormal><span style='font-family:宋体'>这段代码定义了控件的默认状态，即一个梅花图形和一个标签。在给控件添加额外功能之前，首先把这个控件添加到项目的</span><span
lang=EN-US>Web</span><span style='font-family:宋体'>页面</span><span lang=EN-US>WebForm1.aspx</span><span
style='font-family:宋体'>上，测试这个默认状态。</span></p>
<p class=MsoNormal><span style='font-family:宋体'>为了在</span><span lang=EN-US>.aspx</span><span
style='font-family:宋体'>文件中使用定制的控件，首先需要指定如何引用该控件，也就是说，如何在</span><span
lang=EN-US>HTML</span><span style='font-family:宋体'>中引用代表控件的标记名称。为此，在代码的最前面使用</span><span
lang=EN-US><%Register%></span><span style='font-family:宋体'>指令，如下所示。</span></p>
<p class=2 style='margin-top:8.15pt;margin-right:0cm;FTEL:8.15pt;
margin-left:21.45pt;FTEL:18.45pt'><a FTEL="OLE_LINK5"><span lang=EN-US><%@
Register TagPrefix="PCS" TagFTEL="UserC1"
Src="PCSUserC1.ascx" %></span></a></p>
<p class=MsoNormal><span style='font-family:宋体'>属性</span><span lang=EN-US>TagPrefix</span><span
style='font-family:宋体'>和</span><span lang=EN-US>TagName</span><span
style='font-family:宋体'>指定要使用的标记名称</span><span lang=EN-US>(</span><span
style='font-family:宋体'>指定的格式为</span><span lang=EN-US><TagPrefix:TagName>)</span><span
style='font-family:宋体'>，使用属性</span><span lang=EN-US>Src</span><span
style='font-family:宋体'>指向包含用户控件的文件。现在，添加下面的元素，就可以使用控件了：</span></p>
<p class=a6 style='margin-top:8.15pt;margin-right:0cm;FTEL:0cm;
margin-left:21.45pt;FTEL:.0001pt;FTEL:18.45pt'><span
lang=EN-US> <a FTEL="OLE_LINK7"></a><a
FTEL="OLE_LINK6"><form id="Form1" method="post"
runat="server"></a></span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
<PCS:UserC1 Runat="server" ID="<a FTEL="OLE_LINK8">myUserControl</a>"/></span></p>
<p class=a6 style='margin-top:0cm;margin-right:0cm;FTEL:8.15pt;
margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
</form></span></p>
<p class=MsoNormal><span style='font-family:宋体'>在窗体的后台编码文件中，用户控件没有在默认状态下声明，因此也需要给</span><span
lang=EN-US>WebForm1.aspx.cs</span><span style='font-family:宋体'>添加下面的声明：</span></p>
<p class=a6 style='margin-top:8.15pt;margin-right:0cm;FTEL:0cm;
margin-left:21.45pt;FTEL:.0001pt;FTEL:18.45pt'><span
lang=EN-US> public class WebForm1 : System.Web.UI.Page</span></p>
<p class=a6 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
{</span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><a FTEL="OLE_LINK11"><span
lang=EN-US> protected PCSUserC1 myUserControl;</span></a></p>
<p class=a6 style='margin-top:0cm;margin-right:0cm;FTEL:8.15pt;
margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
...</span></p>
<p class=MsoNormal><span style='font-family:宋体'>这就是测试用户控件所需要做的所有工作，运行项目的结果如图</span><span
lang=EN-US>27-2</span><span style='font-family:宋体'>所示。</span></p>
<p align=center><span lang=EN-US><img width=290 height=148
src="27/image002.jpg"></span></p>
<p align=center style='FTEL:8.15pt'><span style='font-family:宋体'>图</span><span
lang=EN-US> 27-2</span></p>
<p class=MsoNormal><span style='font-family:宋体'>可以看出，这个控件组合了两个现有的控件，即图形控件和标签控件，因此它属于合成控件一类。</span></p>
<p class=MsoNormal><span style='font-family:宋体'>为了控制显示的花色图形，可以在元素</span><span
lang=EN-US><PCS:UserC1></span><span style='font-family:宋体'>上使用属性。用户控件元素上的属性会自动映射到用户控件的特性上，因此，只需给控件的后台编码</span><span
lang=EN-US>PCSUserC1.ascx.cs</span><span style='font-family:宋体'>添加特性。这个特性称为</span><span
lang=EN-US>Suit</span><span style='font-family:宋体'>，让它接收合适的花色值。为了便于表示控件的状态，在</span><span
lang=EN-US>PCSUserC1.ascx.cs</span><span style='font-family:宋体'>文件中定义命名空间</span><span
lang=EN-US>PCSUserCWebApp1</span><span style='font-family:宋体'>中的一个枚举，以保存</span><span
lang=EN-US>4</span><span style='font-family:宋体'>个花色名称：</span></p>
<p class=a6 style='margin-top:8.15pt;margin-right:0cm;FTEL:0cm;
margin-left:21.45pt;FTEL:.0001pt;FTEL:18.45pt'><span
lang=EN-US>namespace PCSUserCWebApp1</span></p>
<p class=a6 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>{</span></p>
<p class=a6 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
...</span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><a FTEL="OLE_LINK9"><span
lang=EN-US> public enum suit</span></a></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
{</span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
club, diamond, heart, spade</span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
}</span></p>
<p class=a6 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
...</span></p>
<p class=a6 style='margin-top:0cm;margin-right:0cm;FTEL:8.15pt;
margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>}</span></p>
<p class=MsoNormal><span style='font-family:宋体'>类</span><span lang=EN-US>PCSUserC1</span><span
style='font-family:宋体'>需要一个成员变量，以保存花色类型</span><span lang=EN-US>currentSuit</span><span
style='font-family:宋体'>：</span></p>
<p class=a6 style='margin-top:8.15pt;margin-right:0cm;FTEL:0cm;
margin-left:21.45pt;FTEL:.0001pt;FTEL:18.45pt'><span
lang=EN-US> public class PCSUserC1 : System.Web.UI.UserControl</span></p>
<p class=a6 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
{</span></p>
<p class=a6 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
protected System.Web.UI.WebControls.Image suitPic;</span></p>
<p class=a6 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
protected System.Web.UI.WebControls.Label suitLabel;</span><span
class=MsoCommentReference><span lang=EN-US style='font-size:8.0pt;display:none;
letter-spacing:.2pt'> </span></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>
protected suit currentSuit;</span></p>
<p class=MsoNormal><span style='font-family:宋体'>再添加一个访问这个成员变量的属性</span><span
lang=EN-US>Suit</span><span style='font-family:宋体'>：</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> <a FTEL="OLE_LINK10">public suit Suit</a></span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
{</span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
get</span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
{</span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
return currentSuit;</span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
}</span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
set</span></p>
<p class=2 style='margin-left:21.45pt;FTEL:18.45pt'><span lang=EN-US>
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