本人學Asp.Net不久，用的是C#寫程式碼，在學習C#中發現很多初學者對繼承和多態性不是特別的了解，因此作了這個例子，希望對您有所幫助，例子很簡單
頁面檔案TestProfileClass2.aspx
<%@ Page Language="C#" ContentType="text/html" ResponseEncoding="gb2312" Src="profile2.cs" %>
<%@ Import Namespace="shai" %>
<html>
<head>
<style>
div{font:Arial, Helvetica, sans-serif;
background-color:#cccccc;
border-color:black;
border-width:1;
border-style:solid;
padding:10,10,10,10;
}
</style>
<script language="c#" runat="server">
public void Page_Load(Object sender,EventArgs e)
{
Profile profile = new Profile();
message.InnerHtml += "<u>Profile Class</u><br>";
message.InnerHtml += "Firstname:"+profile.getFirstname()+"<br>";
message.InnerHtml += "Lastname:"+profile.getLastname()+"<br>";
message.InnerHtml += "Phone:"+profile.getPhonenumber()+"<br><br>";
profile.save();
ExtendedProfile extendedprofile = new ExtendedProfile();
message.InnerHtml += "<u>ExtendedProfile Class</u></br>";
message.InnerHtml += "Firstname:"+profile.getFirstname()+"<br>";
message.InnerHtml += "Lastname:"+profile.getLastname()+"<br>";
message.InnerHtml += "Phone:"+extendedprofile.getPhonenumber()+"<br>";
message.InnerHtml += "Address1:"+extendedprofile.getAddress1()+"<br>";
message.InnerHtml += "Address2:"+extendedprofile.getAddress2()+"<br>";
message.InnerHtml += "City:"+extendedprofile.getCity()+"<br>";
message.InnerHtml += "State:"+extendedprofile.getState()+"<br>";
message.InnerHtml += "Postal:"+extendedprofile.getPostal()+"<br>";
message.InnerHtml += "Description:"+extendedprofile.getDescription()+"<br>";
extendedprofile.save();
}
</script>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title></title>
</head>
<body style="font:Arial, Helvetica, sans-serif ">
<b><h3>簡單的繼承/多型範例</h3></b><br><br>
object output:<br>
<br>
<div id="message" runat="server" />
</body>
</html>
類別定義檔profile2.cs
using System;
using System.IO;
using System.Xml;
namespace shai //名稱空間shai
{
interface ISaveData //定義一個介面ISaveData，他作為Profile的基底類別被繼承，由於其有多態性的特點，可以被
{ //不同類別呼叫其中的方法，並修改
void save();
}
public class Profile:ISaveData //定義類別Profile
{
protected string _firstname; //內含三個屬性，分別為_firstname、_lastname、phonenumber
protected string _lastname;
protected string _phonenumber;
public Profile() //為屬性定義其中的初始值
{
_firstname = "Saidy";
_lastname = "Chen";
_phonenumber = "(010)88716990";
}
public string getPhonenumber() //Profile類別中的方法getPhonenumber()
{
return _phonenumber;
}
public virtual void setPhonenumber(string phonenumber)
{
_phonenumber = phonenumber;
}
public string getFirstname() //Profile類別中的方法getFirstname()
{
return _firstname;
}
public void setFirstname(string firstname)
{
_firstname = firstname;
}
public string getLastname() //Profile類別中的方法getLastname()
{
return _lastname;
}
public void setLastname(string lastname)
{
_lastname = lastname;
}
public virtual void save() //呼叫ISaveData介面的save()方法
{
//儲存資料為Text格式
FileStream fs = new FileStream("D:\myweb2\profile2.txt",FileMode.Create,FileAccess.Write);
StreamWriter sw = new StreamWriter(fs);
sw.WriteLine("Firstname:"+_firstname.ToString());
sw.WriteLine("Lastname:"+_lastname.ToString());
sw.WriteLine("Phone:"+_phonenumber.ToString());
sw.Flush();
sw.Close();
fs.Close();
}
}
public class ExtendedProfile:Profile 建立Profile子類別ExtendedProfile，他可以繼承Profile中的方法
{
protected string _address1; //子類別ExtendedProfile的屬性
protected string _address2;
protected string _city;
protected string _state;
protected string _postal;
protected string _description;
public ExtendedProfile() //子類別ExtendedProfile中屬性的初始值
{
_address1 = "清華大學";
_address2 = "清華大學物理實驗室";
_city = "北京";
_state = "北京";
_postal = "100024";
_description = "教授";
}
public override void setPhonenumber(string phonenumber) //繼承類別Profile中的setPhonenumber()方法
{ //setPhonenumber()方法的重載
_phonenumber = phonenumber;
}
public string getAddress1() //子類別ExtendedProfile中的方法getAddress1()，以下類別推
{
return _address1;
}
public string getAddress2()
{
return _address2;
}
public void setAddress(string address1,string address2)
{
_address1 = address1;
_address2 = address2;
}
public string getCity()
{
return _city;
}
public void setCity(string city)
{
_city = city;
}
public string getState()
{
return _state;
}
public void setState(string state)
{
_state = state;
}
public string getPostal()
{
return _postal;
}
public void setPostal(string postal)
{
_postal = postal;
}
public string getDescription()
{
return _description;
}
public void setDescription(string description)
{
_description = description;
}
public override void save() //呼叫介面ISaveData()中的方法save()，save()方法的重載，由於多態性
{ //子類別ExtendedProfile可以自訂並修改save()方法
string _document = "d:\myweb2\saidy.xml";
XmlTextWriter writer = null; //儲存為一個Xml文件
try
{
writer = new XmlTextWriter(_document,null);
writer.Formatting = Formatting.Indented;
writer.WriteStartDocument(false);
writer.WriteDocType("Profile",null,null,null); //表示<!DOCTYPE Profile>
writer.WriteStartElement("Profile"); //產生根元素
writer.WriteElementString("firstname",_firstname); //產生子元素 <firstname>_firstname</firstname>
writer.WriteElementString("lastname",_lastname);
writer.WriteElementString("phonenumber",_phonenumber);
writer.WriteElementString("address1",_address1);
writer.WriteElementString("address2",_address2);
writer.WriteElementString("city",_city);
writer.WriteElementString("state",_state);
writer.WriteElementString("postal",_postal);
writer.WriteEndElement();
writer.Flush();
writer.Close();
}
catch(Exception ee)
{
Console.WriteLine("Exception:{0}",ee.ToString());
}
}
}
}