ASP自定义控件的两种实现方法
1、在HTML中直接调用后台CS代码中的protected成员变量
自定义控件类的HTML代码：
<%@ Control Language="c#" AutoEventWireup="false" Codebehind="MyWebUserControl.ascx.cs" Inherits="WebTestRollback.MyWebUserControl" TargetSchema="http://schemas.microsoft.com/intellisense/ie5"%>
<table width =100%>
<tr bgcolor=#0099ff>
<%
IDictionaryEnumerator objEnumerator = m_htMenu.GetEnumerator();
while (objEnumerator.MoveNext())
{
%>
<td width=10%><a href="<%=(string)objEnumerator.Value%>"><%=(string)objEnumerator.Key%></a>
</td>
<%
}
%>
<td></td>
</tr>
</table>
自定义控件类CS代码：
namespace WebTestRollback
{
using System;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Collections;
/// <summary>
/// </summary>
public class MyWebUserControl : System.Web.UI.UserControl
{
protected Hashtable m_htMenu = new Hashtable();
private void Page_Load(object sender, System.EventArgs e)
{
}
public void AddMenu(string strName,string strLink)
{
m_htMenu.Add(strName,strLink);
}
}
}
2、在自定义控件类中重写Render方法（），此方法不需要控件的HTML代码，只需在Render方法中变相的添加HTML代码，控件的CS代码如下：
namespace WebTestRollback
{
using System;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Collections;
/// <summary>
/// </summary>
public class SubWebUserControl : System.Web.UI.UserControl
{
protected Hashtable m_htMenu = new Hashtable();
private void Page_Load(object sender, System.EventArgs e)
{
}
public void AddMenu(string strName,string strLink)
{
m_htMenu.Add(strName,strLink);
}
protected override void Render(System.Web.UI.HtmlTextWriter writer)
{
base.Render (writer);
writer.Write( @"<table>
<tr>");
IDictionaryEnumerator objEnumerator = m_htMenu.GetEnumerator();
while (objEnumerator.MoveNext())
{
writer.Write( "<td><a href=\""
+ (string)objEnumerator.Value + "\">"
+ (string)objEnumerator.Key
+ "</a></td>");
}
writer.Write(@" <tr> <table>");
}
}
}
两种方法对于自定义控件用户是透明的，使用方法上没有任何区别：
自定义控件用户HTML代码：
<%@ Page language="c#" Codebehind="TestLogin.aspx.cs" AutoEventWireup="false" Inherits="WebTestRollback.TestLogin" %>
<%@ Register TagPrefix="TT" TagName="CC" Src="MyWebUserControl.ascx"%>
<%@ Register TagPrefix="T2" TagName="C2" Src="SubWebUserControl.ascx"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<HTML>
<HEAD>
<title>TestLogin</title>
<meta content="Microsoft Visual Studio .NET 7.1" name="GENERATOR">
<meta content="C#" name="CODE_LANGUAGE">
<meta content="JavaScript" name="vs_defaultClientScript">
<meta content="http://schemas.microsoft.com/intellisense/ie5" name="vs_targetSchema">
</HEAD>
<body bgColor="#33cccc" leftMargin="0" topMargin="0" rightMargin="0" MS_POSITIONING="GridLayout">
<form id="Form1" method="post" Runat="server">
<TT:CC id="m_TTCC" runat="server"></TT:CC>
<T2:C2 id="m_T2C2" runat="server"></T2:C2>
</form>
</body>
</HTML>
自定义控件用户CS代码：
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
namespace WebTestRollback
{
/// <summary>
/// </summary>
public class TestLogin : System.Web.UI.Page
{
public MyWebUserControl m_TTCC = new MyWebUserControl();
public SubWebUserControl m_T2C2 = new SubWebUserControl();
private void Page_Load(object sender, System.EventArgs e)
{
m_TTCC.AddMenu("File","news.sohu.com");
m_TTCC.AddMenu("Edit","hotmail.com");
m_T2C2.AddMenu("Project","project.com");
m_T2C2.AddMenu("Built","built.com");
}
}
}