类定义文件profile2.cs
using System;
using System.IO;
using System.Xml;
namespace shai //名称空间shai
{
interface ISaveData //定义一个接口ISaveData，他作为Profile的基类被继承，由于其有多态性的特点，可以被
{ //不同类调用其中的方法，并修改
void save();
}

public class Profile:ISaveData //定义类Profile
{
protected string _firstname; //里面包含三个属性，分别为_firstname、_lastname、phonenumber
protected string _lastname;
protected string _phonenumber;

public Profile() //为属性定义其中的初始值
{
_firstname = "Saidy";
_lastname = "Chen";
_phonenumber = "(010)88716990";
}

public string getPhonenumber() //Profile类中的方法getPhonenumber()
{
return _phonenumber;
}
public virtual void setPhonenumber(string phonenumber)
{
_phonenumber = phonenumber;
}

public string getFirstname() //Profile类中的方法getFirstname()
{
return _firstname;
}
public void setFirstname(string firstname)
{
_firstname = firstname;
}

public string getLastname() //Profile类中的方法getLastname()
{
return _lastname;
}
public void setLastname(string lastname)
{
_lastname = lastname;
}

public virtual void save() //调用ISaveData接口的save()方法
{
//保存数据为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();
}
}

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