Proxy 为其他对象提供一个代理（surrogate)或者占位符(placeholder),从而完成对其他对象的访问。

using System;
2using System.Data;
3
4namespace DataLayer
5using System;
2using System.Data;
3using DataLayer;
4
5public class LimitingReader : DataReaderProxy
9using System;
2using System.Data;
3using System.Data.OleDb;
4using System.Reflection;
5using System.IO;
6
7namespace Gof.Test.Proxy
8 string sel = "SELECT * FROM ROCKET";
2 Gof.Test.Proxy.DataService.GetDataReader(sel, new Gof.Test.Proxy.BorrowReader(GetNames));
3
4 private static Object GetNames(System.Data.IDataReader reader)
5 {
6 System.Data.IDataReader proxy = new LimitingReader(reader);
7 while (proxy.Read())
8 {
9 Console.Write("{0,10} ", proxy["Name"]);
10 Console.Write("{0,7:C} ", proxy["price"]);
11 Console.Write("{0,5}", proxy["apogee"]);
12 Console.WriteLine();
13 }
14 Console.ReadLine();
15 return null;
16 }