(一). 概述
   通過制作一個<計算器>功能自定義復合控件演示復合控件的制作
(二). 代碼
   1. 核心控件實現代碼文件computecontrol.cs
  1using system;
  2using system.collections.generic;
  3using system.text;
  4using system.web;
  5using system.web.ui;
  6using system.web.ui.webcontrols;
  7
  8namespace kingcontrols
  9{
 10    public class computecontrol : system.web.ui.webcontrols.compositecontrol
 11    {
 12        //操作數
 13        private textbox tb1;
 14        private textbox tb2;
 15
 16        //顯示結果
 17        private label lb;
 18
 19        //操作(+-*/)
 20        private button bt1;
 21        private button bt2;
 22        private button bt3;
 23        private button bt4;
 24
 25        protected override void createchildcontrols()
 26        {
 27            tb1 = new textbox();
 28            tb1.id = "textbox1";
 29            this.controls.add( tb1 );
 30           
 31            tb2 = new textbox();
 32            tb2.id = "textbox2";
 33            this.controls.add(tb2);
 34           
 35            lb = new label();
 36            lb.id = "label1";
 37            lb.backcolor = system.drawing.color.yellowgreen;
 38            lb.text = "result: ";
 39            this.controls.add( lb );
 40           
 41            bt1 = new button();
 42            bt1.id = "button1";
 43            bt1.text = "+";
 44            bt1.commandargument = "+";
 45            bt1.click += new eventhandler(bt_click);
 46            this.controls.add( bt1 );
 47            bt2 = new button();
 48            bt2.id = "button2";
 49            bt2.text = "-";
 50            bt2.commandargument = "-";
 51            bt2.click += new eventhandler(bt_click);
 52            this.controls.add(bt2);
 53            bt3 = new button();
 54            bt3.id = "button3";
 55            bt3.text = "*";
 56            bt3.commandargument = "*";
 57            bt3.click += new eventhandler(bt_click);
 58            this.controls.add(bt3);
 59            bt4 = new button();
 60            bt4.id = "button4";
 61            bt4.text = "/";
 62            bt4.commandargument = "/";
 63            bt4.click += new eventhandler(bt_click);
 64            this.controls.add(bt4);           
 65        }
 66
 67        void bt_click(object sender, eventargs e)
 68        {
 69            try
 70            {
 71                if ("result: " != lb.text)
 72                {
 73                    lb.text = lb.text + ", ";
 74                }
 75                switch( ((button)sender).commandargument  )
 76                {
 77                    case "+": lb.text = lb.text + convert.tostring(convert.toint32(this.tb1.text) + convert.toint32(this.tb2.text)); break;
 78                    case "-": lb.text = lb.text + convert.tostring(convert.toint32(this.tb1.text) - convert.toint32(this.tb2.text)); break;
 79                    case "*": lb.text = lb.text + convert.tostring(convert.toint32(this.tb1.text) * convert.toint32(this.tb2.text)); break;
 80                    case "/": lb.text = lb.text + convert.tostring(convert.toint32(this.tb1.text) / convert.toint32(this.tb2.text)); break;
 81                }
 82            }
 83            catch
 84            {
 85                lb.text = "it's is not right format, please input again.";
 86            }           
 87        }
 88
 89        protected override void rendercontents(htmltextwriter output)
 90        {
 91            output.write("a");
 92
 93        }
 94
 95        protected override void render(htmltextwriter writer)
 96        {
 97            writer.renderbegintag(htmltextwritertag.table);
 98           
 99            //operating item 1
100            writer.renderbegintag(htmltextwritertag.tr);
101            writer.renderbegintag(htmltextwritertag.td);
102            tb1.rendercontrol(writer);
103            writer.renderendtag();
104            writer.renderendtag();
105           
106            //<br>
107            writer.writebreak();
108
109            //operating symbol
110            writer.renderbegintag(htmltextwritertag.tr);
111            writer.renderbegintag(htmltextwritertag.td);
112            writer.writeencodedtext(" + - * / ");
113            writer.renderendtag();
114            writer.renderendtag();
115
116            //operating item2
117            writer.renderbegintag(htmltextwritertag.tr);
118            writer.renderbegintag(htmltextwritertag.td);
119            tb2.rendercontrol(writer);
120            writer.renderendtag();
121            writer.renderendtag();
122
123            //operating symbol
124            writer.renderbegintag(htmltextwritertag.tr);
125            writer.renderbegintag(htmltextwritertag.td);
126            writer.writeencodedtext(" equal ");
127            writer.renderendtag();
128            writer.renderendtag();
129
130            //the relust label
131            writer.renderbegintag(htmltextwritertag.tr);
132            writer.renderbegintag(htmltextwritertag.td);
133            lb.rendercontrol(writer);
134            writer.renderendtag();
135            writer.renderendtag();
136
137            //button1
138            writer.renderbegintag(htmltextwritertag.tr);
139            writer.renderbegintag(htmltextwritertag.nobr);
140            writer.renderbegintag(htmltextwritertag.td);
141            bt1.rendercontrol(writer);                       
142            bt2.rendercontrol(writer);           
143            bt3.rendercontrol(writer);           
144            bt4.rendercontrol(writer);
145            writer.renderendtag();
146            writer.renderendtag();
147
148            writer.renderendtag();
149        }
150    }
151}
152

2. 前臺頁面代碼 usingcompositecontrol.aspx (使用方法)

1<%@ page language="c#" autoeventwireup="true" codefile="usingcompositecontrol.aspx.cs" inherits="usingcompositecontrol" %>
2<%@ register assembly="kingcontrols" namespace="kingcontrols" tagprefix="ksp" %>
3… …
4<ksp:computecontrol id="compute1" runat="server" />
5… …
6
 

(三). 示例代碼下載
        http://www.cnblogs.com/files/chengking/kingcontrols.rar