设计模式：一个简单工厂的问题（c#）

Question

//IShape.cs 图形接口，实现设置中心，画图
using System;
namespace study.designPattern.simpleFactory
{
public interface IShape
{
void setCenter(int x, int y);
void draw();
}
}
//Circle.cs 圆形
using System;
namespace study.designPattern.simpleFactory
{
public class Circle : IShape
{
private int x;
private int y;
public void setCenter(int x, int y)
{
this.x = x;
this.y = y;
}
public void draw()
{
System.Web.HttpContext.Current.Response.Write("Circle center at (" + x + ", " + y + ")");
}
}
}
//ShapeFactory.cs 生产图形工厂
using System;
namespace study.designPattern.simpleFactory
{
public class ShapeFactory
{
public static IShape createShapeAt(string name, int x, int y)
{
try
{
                                    //这个地方不知道怎么写
return shape;
}
catch(Exception ex)
{
System.Web.HttpContext.Current.Response.Write(ex.Message);
return null;
}
}
}
}
//ShapeFactory.cs 生产图形工厂不知道怎么写，请指教

Answer 1

if (name="circle")
{
  return new Circle(x,y);
}
else if (name = "shape1")
{
 reurn new Shape1(x,y);
}
类似这样的，当然返回的对象都要实现IShape接口

Answer 2

谢谢 Zoujinyucn(不会游泳的鱼)
//java中是这样实现的
IShape shape = (IShape) Class.forName(name).newInstance();
shape.setCenter(x, y);
return shape;
//.net应该怎么实现呢？

Answer 3

...
//name应该定义为枚举
                            try
{
                                switch(name)
                                {
                                     case "Circle":
                                          return new Circle();
                                     case "Rectangle":
                                          return new Rectange();
                                     //other sharp...
                                     default:
                                     //我觉得应该再定义一个基类的...
                                          return null;
                                }    
}
catch(Exception ex)
{
System.Web.HttpContext.Current.Response.Write(ex.Message);
return null;
}
...

Answer 4

谢谢 Zoujinyucn(不会游泳的鱼)
//java中是这样实现的
IShape shape = (IShape) Class.forName(name).newInstance();
shape.setCenter(x, y);
return shape;.net
里面也有反射,你可以看看PepShop3.0这个是我写的,
/// <summary>
/// 业务适配的工厂类,负责实例化业务适配,如果实例化失败,返回null
/// </summary>
public  class AdapterFactory
{
private static string RunLogPath=System.Configuration.ConfigurationSettings.AppSettings["RunLogPath"];
public static IBusinessAdapter Create(string adapterName)
{

IBusinessAdapter adapter=null;
if (adapterName==null||adapterName.Length==0)
return adapter;
try
{
string path = System.Configuration.ConfigurationSettings.AppSettings["BusinessAdapterPath"];
string className = path+ "."+adapterName;
path=path.Substring(path.LastIndexOf(".")+1);
return (IBusinessAdapter) Assembly.Load(path).CreateInstance(className);

}
catch(Exception ex)
{
ExceptionManager.Publish(ex);
VNetLog.WriteSysLog(RunLogPath,VNetLogSource.VNetPHSSelfSupport,VNetLogType.Exception
,"adapterName ="+adapterName
,"初始化业务适配发生异常"
,"",3);
}
return adapter;
}
}

Answer 5

ask： listhome(不想睡)(好好学习)
string className = path+ "."+adapterName;
classname是完整的namespace名字吗？