原文地址：http://www.cnblogs.com/leoo2sk/archive/2009/06/17/1504693.html
里面有一个例子差了些代码，补全后贴上。
3.1.3 依赖获取
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Xml;//定义了三个接口 IWindow IButton ITextBox namespace DependencyLocate {internal interface IWindow{String ShowInfo();}internal interface IButton{String ShowInfo();}internal interface ITextBox{String ShowInfo();} }//实现接口 IWindow， 实现类 WindowsWindow、MacWindow namespace DependencyLocate {internal sealed class WindowsWindow : IWindow{public String Description { get; private set; }public WindowsWindow(){this.Description = "Windows风格窗体";}public String ShowInfo(){return this.Description;}}internal sealed class MacWindow : IWindow{public String Description { get; private set; }public MacWindow(){this.Description = " Mac风格窗体";}public String ShowInfo(){return this.Description;}} }//实现接口 IButton， 实现类 WindowsButton、MacButton namespace DependencyLocate {internal sealed class WindowsButton : IButton{public String Description { get; private set; }public WindowsButton(){this.Description = "Windows风格按钮";}public String ShowInfo(){return this.Description;}}internal sealed class MacButton : IButton{public String Description { get; private set; }public MacButton(){this.Description = " Mac风格按钮";}public String ShowInfo(){return this.Description;}} }//实现接口 ITextBox， 实现类 WindowsTextBox、MacTextBox namespace DependencyLocate {internal sealed class WindowsTextBox : ITextBox{public String Description { get; private set; }public WindowsTextBox(){this.Description = "Windows风格文本框";}public String ShowInfo(){return this.Description;}}internal sealed class MacTextBox : ITextBox{public String Description { get; private set; }public MacTextBox(){this.Description = " Mac风格文本框";}public String ShowInfo(){return this.Description;}} }namespace DependencyLocate {internal interface IFactory{IWindow MakeWindow();IButton MakeButton();ITextBox MakeTextBox();} }namespace DependencyLocate {internal sealed class WindowsFactory : IFactory{public IWindow MakeWindow(){return new WindowsWindow();}public IButton MakeButton(){return new WindowsButton();}public ITextBox MakeTextBox(){return new WindowsTextBox();}} }namespace DependencyLocate {internal sealed class MacFactory : IFactory{public IWindow MakeWindow(){return new MacWindow();}public IButton MakeButton(){return new MacButton();}public ITextBox MakeTextBox(){return new MacTextBox();}} }namespace DependencyLocate {internal static class FactoryContainer{public static IFactory factory { get; private set; }/// <summary>/// 静态构造函数：/// 是一个特殊的函数，将在其他所有方法执行之前以及变量或属性被第一次访问之前执行。/// 这个构造函数是属于类的，而不是属于哪里实例的，就是说这个构造函数只会被执行一次。/// 也就是在创建第一个实例或引用任何静态成员之前，由.NET自动调用。/// 可以使用该函数来初始化静态变量，不应该使用实例构造函数初始化静态变量。/// 地址：https://www.cnblogs.com/aimi/p/5499711.html/// </summary>static FactoryContainer(){XmlDocument xmlDoc = new XmlDocument();xmlDoc.Load("Config.xml");XmlNode xmlNode = xmlDoc.ChildNodes[1].ChildNodes[0].ChildNodes[0];if ("Windows" == xmlNode.Value){factory = new WindowsFactory();}else if ("Mac" == xmlNode.Value){factory = new MacFactory();}else{throw new Exception("Factory Init Error");}}} }namespace DependencyLocate {class Program{static void Main(string[] args){IFactory factory = FactoryContainer.factory;IWindow window = factory.MakeWindow();Console.WriteLine("创建 " + window.ShowInfo());IButton button = factory.MakeButton();Console.WriteLine("创建 " + button.ShowInfo());ITextBox textBox = factory.MakeTextBox();Console.WriteLine("创建 " + textBox.ShowInfo());Console.ReadLine();}} }
