享元模式

/*
 * User: Administrator
 * Date: 2007-7-3 Time: 14:16
  */

using  System;
using  System.Windows.Forms;
using  System.Reflection;
using  System.Runtime.Remoting;
using  System.Collections;

namespace  myMemonto
{
     ///   <summary>
     ///  Description of MyShare.
     ///   </summary>
     public   class  MyShare
    {
         public  MyShare()
        {
        }
    }
     public   class  ApartmentType{
         public   string  TypeCode;
         public   string  TypeName;
         public  ApartmentType(){

        }
    }
     public   class  Apartment{
         protected   string  name;
         protected   string  ap_type;
         public   string  roomNumber;
         public   double  area;

         private  Form editform;
         public  Apartment()
        {
            editform = FlyWightFactory.GetEditForm( " myMemonto.EditApartment " );
             // editform=new EditApartment();
        }
         protected  Apartment myType;

         public   string  Name{
             get { return  name;}
             set {name = value;}
        }

         public   string  ApartmentType{
             get { return  ap_type;}
             set {ap_type = value;}
        }

         public   virtual   bool  Edit(){
            EditApartment f = (EditApartment)editform;
            f.txtName.Text = name;
            f.txtArea.Text = area.ToString();
            f.txtType.Text = ap_type;
            f.txtRoomNumber.Text = roomNumber;


             if (f.ShowDialog() ==  DialogResult.OK){

                name = f.txtName.Text;
                area = double .Parse(f.txtArea.Text);
                ap_type = f.txtType.Text;
                roomNumber = f.txtRoomNumber.Text;

                MessageBox.Show( " saved " );
                 return   true ;
            }
             else
            {
                MessageBox.Show( " cancelled " );
                 return   false ;
            }

        }

         public   string  RoomNumber{
             get { return  roomNumber;}
             set {roomNumber = value;}
        }
         public   double  Area{
             get { return  area;}
             set {area = value;}
        }
         public   override   string  ToString()
        {
             return  name;
        }
    }


     public   class  TestaEditForm
    {
         private  Form editform;
         public  TestaEditForm(){
            editform = FlyWightFactory.GetEditForm( " myMemonto.MyTest " );
        }

         public   bool  Edit()
        {
            MyTest a = (myMemonto.MyTest)editform;
             if (a.ShowDialog() ==  DialogResult.OK)
            {
                MessageBox.Show( " Saved " );
                 return   true ;
            }
             else
            {
                MessageBox.Show( " canceled " );
                 return   false ;
            }
        }
         public  Form EditForm{
             get { return  editform;}
             set {editform = value;}
        }

    }

     public   class  TypeFacotry{
         public  TypeFacotry(){}
         private   static  ArrayList types = new  ArrayList();

         public   static  ApartmentType GetApartmentType( string  typecode){
             foreach (ApartmentType at  in  types){
                 if (at.TypeCode == typecode)  return  at;
            }

            ApartmentType nat = new  ApartmentType();
            nat.TypeCode = typecode;
            nat.TypeCode = typecode;

            types.Add(nat);
             return  nat;
        }
    }

     public   class  FlyWightFactory{
         private   static  ArrayList editforms = new  ArrayList();

         private  FlyWightFactory(){}

         public   static  Form GetEditForm( string  formType)
        {
            Form editform;
             foreach (Form ef  in  editforms)
                 if (ef.GetType().Name == formType)  return  ef;

            ObjectHandle obj = Activator.CreateInstance( null ,formType);
            editform = (Form)obj.Unwrap();

            editforms.Add(editform);

             return  editform;
        }
    }


}

void  Button1Click( object  sender, EventArgs e)
{
    Apartment newa = new  Apartment();
     if (newa.Edit()) this .listBox1.Items.Add(newa);
}

void  Button2Click( object  sender, EventArgs e)
{
    Apartment a = (Apartment)  this .listBox1.SelectedItem;
     if (a != null ) a.Edit();
}

void  Button4Click( object  sender, EventArgs e)
{
    TestaEditForm b = new  TestaEditForm();
     if (b.Edit())  this .listBox1.Items.Add(b);
}