1. 接口和抽象类有很多共同点, 都是声明变量, 不能被实例化. 并且其中的方法都不提供实现代码.
2. 接口的任何派生类型(类或接口)都必须继承该接口定义的所有方法, 并且其派生类如果是非抽象的, 则必须实现接口的所有方法.
抽象类的派生类必须继承其所有抽象方法, 并且其派生类如果是非抽象的, 则必须实现抽象类的所有抽象方法.
3. 接口抽象化更高, 接口的方法全是抽象方法, 而抽象类中的方法可以有抽象方法也可以有非抽象方法. 另外, 接口还不能有字段成员.
4. 如果派生类既继承了类又继承了接口, 则定义时先写基类再写接口. 如: class creditcard : bankcard,Iloan
接口定义时 方法上不用访问限制修饰符.
多接口定义了相同方法, 而派生类又继承了这些接口, 则用一个方法即可实现. 如果要区分, 可以用 "接口名.方法名" 写多个相同方法.
using System;
using System.Collections.Generic;
using System.Text;
namespace ConsoleApp
{
class InheritSample
{
public static void Main()
{
Business c1 = new Business("赵丽");
c1.title = "经理";
c1["办公电话"] = "010-1234567";
Family c2 = new Family("王强");
c2.Relation = "表弟";
c2.Birthday = new DateTime(1980, 12, 1);
c2["手机"] = "13801284321";
//因为Bussiness通过重载Output方法实现多态,故强两次调用output方法的输出是相同的
c1.Output();
Console.WriteLine("----------------------------");
((Contact)c1).Output();
Console.WriteLine("----------------------------");
((IOutput)c1).Output();
Console.WriteLine("----------------------------");
c2.Output();
Console.WriteLine("----------------------------");
((Contact)c2).Output();
Console.Read();
}
}
//接口:可输出IOutput
public interface IOutput
{
void Output();
}
public class Contact : IOutput, IComparable
{
protected string m_name;
protected string m_homePhone = "未知";
protected string m_busiPhone = "未知";
protected string m_mobilePhone = "未知";
public string Name
{
get { return m_name; }
set { m_name = value; }
}
public virtual string this[string phoneType] //带参数分支的属性 索引函数
{
get
{
switch (phoneType)
{
case "住宅电话":
return m_homePhone;
case "办公电话":
return m_busiPhone;
case "手机":
return m_mobilePhone;
default:
return null;
}
}
set
{
switch (phoneType)
{
case "住宅电话":
m_homePhone = value;
break;
case "办公电话":
m_busiPhone = value;
break;
case "手机":
m_mobilePhone = value;
break;
default:
break;
}
}
}
public Contact(string name)
{
m_name = name;
}
public virtual void Output()
{
Console.WriteLine("姓名:{0}", m_name);
Console.WriteLine("住宅电话:{0}", m_homePhone);
Console.WriteLine("办公电话:{0}", m_busiPhone);
Console.WriteLine("手机:{0}", m_mobilePhone);
}
public int CompareTo(object obj)
{
if (obj is Contact)
{
return m_name.CompareTo(((Contact)obj).m_name);
}
return -1;
}
}
//派生类:商务Business
public class Business : Contact, IOutput
{
protected string m_busiFax = "未知";
protected string m_title = "女士/先生";
public string title
{
get { return m_title; }
set { m_title = value; }
}
public override string this[string phoneType]
{
//使用base简化为↓
get
{
switch (phoneType)
{
case "传真":
return m_busiFax;
default:
return base[phoneType];
}
}
set
{
switch (phoneType)
{
case "传真":
m_busiFax = value;
break;
default:
base[phoneType] = value;
break;
}
}
}
public Business(string name) : base(name) { }
//重载基类方法
public override void Output()
{
base.Output();
Console.WriteLine("传真:{0}", m_busiFax);
}
//实现接口方法
void IOutput.Output()
{
Console.WriteLine(m_name + m_title);
Console.WriteLine("(B){0} (F){1} (H){2} (M){3} ", m_busiPhone, m_busiFax, m_homePhone, m_mobilePhone);
}
}
public class Family : Contact
{
protected string m_relation;
protected DateTime m_birthday;
public string Relation
{
get { return m_relation; }
set { m_relation = value; }
}
public DateTime Birthday
{
get { return m_birthday; }
set { m_birthday = value; }
}
public Family(string name) : base(name) { }
//覆盖
public new void Output()
{
Console.WriteLine(m_relation + m_name);
Console.WriteLine("生日:{0}", m_birthday);
Console.WriteLine("(B){0} (H){1} (M){2} ", m_busiPhone, m_homePhone, m_mobilePhone);
}
}
}
姓名:赵丽
住宅电话:未知
办公电话:010-1234567
手机:未知
传真:未知
----------------------------
姓名:赵丽
住宅电话:未知
办公电话:010-1234567
手机:未知
传真:未知
----------------------------
赵丽经理
(B)010-1234567 (F)未知 (H)未知 (M)未知
----------------------------
表弟王强
生日:1980-12-1 0:00:00
(B)未知 (H)未知 (M)13801284321
----------------------------
姓名:王强
住宅电话:未知
办公电话:未知
手机:13801284321
http://www.cnblogs.com/streetpasser/archive/2012/11/30/2796337.html <ConsoleApp2引入ConsoleApp>
using System;
using System.Collections.Generic;
using System.Text;
using ConsoleApp; //引入
namespace ConsoleApp
{
class InheritSample2
{
public static void Main()
{
Business c1 = new Business("赵丽");
c1.title = "经理";
c1["办公电话"] = "010-1234567";
Family c2 = new Family("王强");
c2.Relation = "表弟";
c2.Birthday = new DateTime(1980, 12, 1);
c2["手机"] = "13801284321";
//调用
ContactAssemble asm = new ContactAssemble(10);
asm.SetAt(0,c1);
asm.SetAt(1, c2);
asm.Output();
Console.WriteLine();
((IOutput )asm).Output();
Console.Read();
}
}
//集合接口 -- 可使用不同的数据结构来实现
public interface IAssemble
{
int length { get;} //取得集合长度
object GetAt(int index); //读取集合元素
void SetAt(int index, object obj); //设置集合元素
}
//抽象类: 集合CzAssemble
public abstract class CzAssemble : IAssemble
{
protected object[] m_list;
public int length
{
get { return m_list.Length; }
}
public CzAssemble(int length)
{
m_list = new object[length];
}
public virtual object GetAt(int index)
{
return m_list[index];
}
public virtual void SetAt(int index, object obj)
{
m_list[index] = obj;
}
}
//派生类:联系人集合
public class ContactAssemble : CzAssemble, IOutput
{
public ContactAssemble(int length) : base(length) { }
public new Contact GetAt(int index)
{
return (Contact)m_list[index];
}
public void SetAt(int index, Contact c)
{
m_list[index] = c;
}
public void Output()
{
foreach (Contact c in m_list)
{
if (c != null)
{
c.Output();
Console.WriteLine("-------------------------");
}
}
}
void IOutput.Output()
{
foreach (Contact c in m_list)
{
if (c != null)
{
((IOutput )c).Output();
Console.WriteLine("-------------------------");
}
}
}
}
}
姓名:赵丽
住宅电话:未知
办公电话:010-1234567
手机:未知
传真:未知
-------------------------
姓名:王强
住宅电话:未知
办公电话:未知
手机:13801284321
-------------------------
赵丽经理
(B)010-1234567 (F)未知 (H)未知 (M)未知
-------------------------
姓名:王强
住宅电话:未知
办公电话:未知
手机:13801284321
-------------------------
使用ArrayList
using System;
using System.Collections.Generic;
using System.Text;
using System.Collections ;
using ConsoleApp; //引入
namespace ConsoleAppl3
{
class InheritSample3
{
static void Main(string[] args)
{
Business c1 = new Business("赵丽");
c1.title = "经理";
c1["办公电话"] = "010-1234567";
Family c2 = new Family("王强");
c2.Relation = "表弟";
c2.Birthday = new DateTime(1980, 12, 1);
c2["手机"] = "13801284321";
ContactAssemble asm = new ContactAssemble(10);
asm.Add(c1);
asm.Add(c2);
asm.Output();
Console.WriteLine();
((IOutput)asm).Output();
Console.Read();
}
}
public class ContactAssemble : ArrayList, IOutput
{
public ContactAssemble(int length) : base(length) { }
public void Output()
{
foreach (Contact c in this)
{
if (c != null)
{
c.Output();
Console.WriteLine("-----------------------------------");
}
}
}
void IOutput.Output()
{
foreach (Contact c in this)
{
if (c != null)
{
((IOutput )c).Output();
Console.WriteLine("-----------------------------------");
}
}
}
}
}