原文:
乐在其中设计模式(C#) - 桥接模式(Bridge Pattern)
作者： webabcd
介绍
将抽象部分与它的实现部分分离，使它们都可以独立地变化。
示例
有一个Message实体类，对它的操作有Insert()和Get()方法，现在使这些操作的抽象部分和实现部分分离。
MessageModel
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{
/// <summary>
/// Message实体类
/// </summary>
public class MessageModel
{
/// <summary>
/// 构造函数
/// </summary>
/// <param name="msg">Message内容</param>
/// <param name="pt">Message发布时间</param>
public MessageModel(string msg, DateTime pt)
{
this._message = msg;
this._publishTime = pt;
}
private string _message;
/// <summary>
/// Message内容
/// </summary>
public string Message
{
get { return _message; }
set { _message = value; }
}
private DateTime _publishTime;
/// <summary>
/// Message发布时间
/// </summary>
public DateTime PublishTime
{
get { return _publishTime; }
set { _publishTime = value; }
}
}
}
Message
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{
/// <summary>
/// 操作Message（Abstraction）
/// </summary>
public class Message
{
private AbstractMessage _abstractMessage;
/// <summary>
/// 操作Message（Implementor）
/// </summary>
public AbstractMessage AbstractMessage
{
get { return _abstractMessage; }
set { _abstractMessage = value; }
}
/// <summary>
/// 获取Message
/// </summary>
/// <returns></returns>
public virtual List<MessageModel> Get()
{
return _abstractMessage.Get();
}
/// <summary>
/// 插入Message
/// </summary>
/// <param name="mm">Message实体对象</param>
/// <returns></returns>
public virtual bool Insert(MessageModel mm)
{
return _abstractMessage.Insert(mm);
}
}
}
MyMessage
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{
/// <summary>
/// 操作Message（RefinedAbstraction）
/// </summary>
public class MyMessage : Message
{
/// <summary>
/// 获取Message
/// </summary>
/// <returns></returns>
public override List<MessageModel> Get()
{
List<MessageModel> l = base.Get();
foreach (MessageModel mm in l)
{
mm.Message += "（RefinedAbstraction）";
}
return l;
}
}
}
AbstractMessage
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{
/// <summary>
/// 操作Message（Implementor）
/// </summary>
public abstract class AbstractMessage
{
/// <summary>
/// 获取Message
/// </summary>
/// <returns></returns>
public abstract List<MessageModel> Get();
/// <summary>
/// 插入Message
/// </summary>
/// <param name="mm">Message实体对象</param>
/// <returns></returns>
public abstract bool Insert(MessageModel mm);
}
}
SqlMessage
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{
/// <summary>
/// Sql方式操作Message（ConcreteImplementor）
/// </summary>
public class SqlMessage : AbstractMessage
{
/// <summary>
/// 获取Message
/// </summary>
/// <returns></returns>
public override List<MessageModel> Get()
{
List<MessageModel> l = new List<MessageModel>();
l.Add(new MessageModel("SQL方式获取Message", DateTime.Now));
return l;
}
/// <summary>
/// 插入Message
/// </summary>
/// <param name="mm">Message实体对象</param>
/// <returns></returns>
public override bool Insert(MessageModel mm)
{
// 代码略
return true;
}
}
}
XmlMessage
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{
/// <summary>
/// Xml方式操作Message（ConcreteImplementor）
/// </summary>
public class XmlMessage : AbstractMessage
{
/// <summary>
/// 获取Message
/// </summary>
/// <returns></returns>
public override List<MessageModel> Get()
{
List<MessageModel> l = new List<MessageModel>();
l.Add(new MessageModel("XML方式获取Message", DateTime.Now));
return l;
}
/// <summary>
/// 插入Message
/// </summary>
/// <param name="mm">Message实体对象</param>
/// <returns></returns>
public override bool Insert(MessageModel mm)
{
// 代码略
return true;
}
}
}
Test
using
System;
using
System.Data;
using
System.Configuration;
using
System.Collections;
using
System.Web;
using
System.Web.Security;
using
System.Web.UI;
using
System.Web.UI.WebControls;
using
System.Web.UI.WebControls.WebParts;
using
System.Web.UI.HtmlControls;
using
Pattern.Bridge;
public
partial
class
Bridge : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
MyMessage m = new MyMessage();
m.AbstractMessage = new SqlMessage();
Response.Write(m.Insert(new MessageModel("插入", DateTime.Now)));
Response.Write("<br />");
Response.Write(m.Get()[0].Message + " " + m.Get()[0].PublishTime.ToString());
Response.Write("<br />");
m.AbstractMessage = new XmlMessage();
Response.Write(m.Insert(new MessageModel("插入", DateTime.Now)));
Response.Write("<br />");
Response.Write(m.Get()[0].Message + " " + m.Get()[0].PublishTime.ToString());
}
}
运行结果
True
SQL方式获取Message（RefinedAbstraction） 2007-5-13 19:11:19
True
XML方式获取Message（RefinedAbstraction） 2007-5-13 19:11:19
参考
http://www.dofactory.com/Patterns/PatternBridge.aspx
OK
[源码下载]
乐在其中设计模式(C#) - 桥接模式(Bridge Pattern)
作者： webabcd
介绍
将抽象部分与它的实现部分分离，使它们都可以独立地变化。
示例
有一个Message实体类，对它的操作有Insert()和Get()方法，现在使这些操作的抽象部分和实现部分分离。
MessageModel
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{
/// <summary> /// Message实体类 /// </summary> public class MessageModel { /// <summary> /// 构造函数 /// </summary> /// <param name="msg">Message内容</param> /// <param name="pt">Message发布时间</param> public MessageModel(string msg, DateTime pt) { this._message = msg; this._publishTime = pt; } private string _message; /// <summary> /// Message内容 /// </summary> public string Message { get { return _message; } set { _message = value; } } private DateTime _publishTime; /// <summary> /// Message发布时间 /// </summary> public DateTime PublishTime { get { return _publishTime; } set { _publishTime = value; } } }}
Message
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{ /// <summary> /// 操作Message（Abstraction） /// </summary> public class Message { private AbstractMessage _abstractMessage; /// <summary> /// 操作Message（Implementor） /// </summary> public AbstractMessage AbstractMessage { get { return _abstractMessage; } set { _abstractMessage = value; } } /// <summary> /// 获取Message /// </summary> /// <returns></returns> public virtual List<MessageModel> Get() { return _abstractMessage.Get(); } /// <summary> /// 插入Message /// </summary> /// <param name="mm">Message实体对象</param> /// <returns></returns> public virtual bool Insert(MessageModel mm) { return _abstractMessage.Insert(mm); } }}
MyMessage
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{ /// <summary> /// 操作Message（RefinedAbstraction） /// </summary> public class MyMessage : Message { /// <summary> /// 获取Message /// </summary> /// <returns></returns> public override List<MessageModel> Get() { List<MessageModel> l = base.Get(); foreach (MessageModel mm in l) { mm.Message += "（RefinedAbstraction）"; } return l; } }}
AbstractMessage
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{ /// <summary> /// 操作Message（Implementor） /// </summary> public abstract class AbstractMessage { /// <summary> /// 获取Message /// </summary> /// <returns></returns> public abstract List<MessageModel> Get(); /// <summary> /// 插入Message /// </summary> /// <param name="mm">Message实体对象</param> /// <returns></returns> public abstract bool Insert(MessageModel mm); }}
SqlMessage
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{ /// <summary> /// Sql方式操作Message（ConcreteImplementor） /// </summary> public class SqlMessage : AbstractMessage { /// <summary> /// 获取Message /// </summary> /// <returns></returns> public override List<MessageModel> Get() { List<MessageModel> l = new List<MessageModel>(); l.Add(new MessageModel("SQL方式获取Message", DateTime.Now)); return l; } /// <summary> /// 插入Message /// </summary> /// <param name="mm">Message实体对象</param> /// <returns></returns> public override bool Insert(MessageModel mm) { // 代码略 return true; } }}
XmlMessage
using
System;
using
System.Collections.Generic;
using
System.Text;
namespace
Pattern.Bridge
{ /// <summary> /// Xml方式操作Message（ConcreteImplementor） /// </summary> public class XmlMessage : AbstractMessage { /// <summary> /// 获取Message /// </summary> /// <returns></returns> public override List<MessageModel> Get() { List<MessageModel> l = new List<MessageModel>(); l.Add(new MessageModel("XML方式获取Message", DateTime.Now)); return l; } /// <summary> /// 插入Message /// </summary> /// <param name="mm">Message实体对象</param> /// <returns></returns> public override bool Insert(MessageModel mm) { // 代码略 return true; } }}
Test
using
System;
using
System.Data;
using
System.Configuration;
using
System.Collections;
using
System.Web;
using
System.Web.Security;
using
System.Web.UI;
using
System.Web.UI.WebControls;
using
System.Web.UI.WebControls.WebParts;
using
System.Web.UI.HtmlControls;
using
Pattern.Bridge;
public
partial
class
Bridge : System.Web.UI.Page
{ protected void Page_Load(object sender, EventArgs e) { MyMessage m = new MyMessage(); m.AbstractMessage = new SqlMessage(); Response.Write(m.Insert(new MessageModel("插入", DateTime.Now))); Response.Write("<br />"); Response.Write(m.Get()[0].Message + " " + m.Get()[0].PublishTime.ToString()); Response.Write("<br />"); m.AbstractMessage = new XmlMessage(); Response.Write(m.Insert(new MessageModel("插入", DateTime.Now))); Response.Write("<br />"); Response.Write(m.Get()[0].Message + " " + m.Get()[0].PublishTime.ToString()); }}
运行结果
True
SQL方式获取Message（RefinedAbstraction） 2007-5-13 19:11:19
True
XML方式获取Message（RefinedAbstraction） 2007-5-13 19:11:19
参考
http://www.dofactory.com/Patterns/PatternBridge.aspx
OK
[源码下载]
