Csharp: Builder Patterns

/// <summary>
    /// Summary description for Equities.
    /// geovindu,Geovin Du,涂聚文
    /// 生成器(建造)模式（Builder Patterns)
    /// </summary>
    public abstract class Equities
    {
        protected ArrayList array;

        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public abstract string ToString();
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public ArrayList getNames()
        {
            return array;
        }
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
	
        public int count()
        {
            return array.Count;
        }
    }

  /// <summary>
    /// Summary description for Stocks.
    /// geovindu,Geovin Du,涂聚文
    /// 生成器(建造)模式（Builder Patterns)
    /// </summary>
    public class Stocks : Equities
    {

        /// <summary>
        /// 
        /// </summary>
        public Stocks()
        {
            array = new ArrayList();
            array.Add("Cisco");
            array.Add("Coca Cola");
            array.Add("GE");
            array.Add("Harley Davidson");
            array.Add("IBM");
            array.Add("Microsoft");
        }

        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public override string ToString()
        {
            return "Stocks";
        }
    }

/// <summary>
    /// Summary description for Bonds.
    /// geovindu,Geovin Du,涂聚文
    /// 生成器(建造)模式（Builder Patterns)
    /// </summary>
    public class Bonds : Equities
    {

        /// <summary>
        /// 
        /// </summary>
        public Bonds()
        {
            array = new ArrayList();
            array.Add("CT GO 2005");
            array.Add("NY GO 2012");
            array.Add("GE Corp Bonds");
        }
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public override string ToString()
        {
            return "Bonds";
        }
    }

/// <summary>
    /// Summary description for Mutuals.
    /// geovindu,Geovin Du,涂聚文
    /// 生成器(建造)模式（Builder Patterns)
    /// </summary>
    public class Mutuals : Equities
    {

        /// <summary>
        /// 
        /// </summary>
        public Mutuals()
        {
            array = new ArrayList();
            array.Add("Fidelity Magellan");
            array.Add("Lindner");
            array.Add("T Rowe Price");
            array.Add("Vanguard Primecap");

        }

        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public override string ToString()
        {
            return "Mutuals";
        }
    }

 /// <summary>
    /// Summary description for MultiChoice.
    /// geovindu,Geovin Du,涂聚文
    /// 生成器(建造)模式（Builder Patterns)
    /// </summary>
    public interface MultiChoice
    {
        ArrayList getSelected();
        void clear();
        Panel getWindow();
    }

/// <summary>
    /// 
    /// geovindu,Geovin Du,涂聚文
    /// 生成器(建造)模式（Builder Patterns)
    /// </summary>
    public class CheckChoice : MultiChoice
    {
        private ArrayList stocks;
        private Panel panel;
        private ArrayList boxes;
        /// <summary>
        /// 
        /// </summary>
        /// <param name="stks"></param>
        public CheckChoice(Equities stks)
        {
            stocks = stks.getNames();
            panel = new Panel();
            boxes = new ArrayList();
            //add the check boxes to the panel
            for (int i = 0; i < stocks.Count; i++)
            {
                CheckBox ck = new CheckBox();
                //position them
                ck.Location = new Point(8, 16 + i * 32);
                string stk = (string)stocks[i];
                ck.Text = stk;
                ck.Size = new Size(112, 24);
                ck.TabIndex = 0;
                ck.TextAlign = ContentAlignment.MiddleLeft;
                boxes.Add(ck);
                panel.Controls.Add(ck);
            }
        }
   
        /// <summary>
        /// uncheck all check boxes
        /// </summary>
        public void clear()
        {
            for (int i = 0; i < boxes.Count; i++)
            {
                CheckBox ck = (CheckBox)boxes[i];
                ck.Checked = false;
            }
        }
    
        /// <summary>
        /// return list of checked items
        /// </summary>
        /// <returns></returns>
        public ArrayList getSelected()
        {
            ArrayList sels = new ArrayList();
            for (int i = 0; i < boxes.Count; i++)
            {
                CheckBox ck = (CheckBox)boxes[i];
                if (ck.Checked)
                {
                    sels.Add(ck.Text);
                }
            }
            return sels;
        }
    
        /// <summary>
        /// return panel of checkboxes
        /// </summary>
        /// <returns></returns>
        public Panel getWindow()
        {
            return panel;
        }
    }

 /// <summary>
    /// Summary description for ListChoice.
    /// geovindu,Geovin Du,涂聚文
    /// 生成器(建造)模式（Builder Patterns)
    /// </summary>
    /// creates a Panel containing a list box
    public class ListChoice : MultiChoice
    {
        private ArrayList stocks;
        private Panel panel;
        private ListBox list;
    

        /// <summary>
        /// constructor creates and loads the list box
        /// </summary>
        /// <param name="stks"></param>
        public ListChoice(Equities stks)
        {
            stocks = stks.getNames();
            panel = new Panel();
            list = new ListBox();
            list.Location = new Point(16, 0);
            list.Size = new Size(120, 160);
            list.SelectionMode = SelectionMode.MultiExtended;
            list.TabIndex = 0;
            panel.Controls.Add(list);
            for (int i = 0; i < stocks.Count; i++)
            {
                list.Items.Add(stocks[i]);
            }
        }
        
        /// <summary>
        /// returns the Panel
        /// </summary>
        /// <returns></returns>
        public Panel getWindow()
        {
            return panel;
        }
      
        /// <summary>
        /// returns an array of selected elements
        /// </summary>
        /// <returns></returns>
        public ArrayList getSelected()
        {
            ArrayList sels = new ArrayList();
            ListBox.SelectedObjectCollection coll = list.SelectedItems;
            for (int i = 0; i < coll.Count; i++)
            {
                string item = (string)coll[i];
                sels.Add(item);
            }
            return sels;
        }
     
        /// <summary>
        /// clear selected elements
        /// </summary>
        public void clear()
        {
            list.Items.Clear();
        }
    }

 /// <summary>
    /// Summary description for StockFactory.
    /// </summary>
    public class StockFactory
    {

        /// <summary>
        /// 
        /// </summary>
        /// <param name="stocks"></param>
        /// <returns></returns>
        public static MultiChoice getBuilder(Equities stocks)
        {
            if (stocks.count() <= 3)
            {
                return new CheckChoice(stocks);
            }
            else
            {
                return new ListChoice(stocks);
            }
        }
    }

窗体调用测试：

    /// <summary>
    /// 建造者模式（Builder Pattern) 
    /// Geovin Du 涂聚文
    /// </summary>
    public partial class BuilderPatternsForm : Form
    {
        private MultiChoice mchoice;


        /// <summary>
        /// 
        /// </summary>
        private void init()
        {
            lsEquities.Items.Add(new Stocks());
            lsEquities.Items.Add(new Bonds());
            lsEquities.Items.Add(new Mutuals());
        }
        /// <summary>
        /// 
        /// </summary>
        public BuilderPatternsForm()
        {
            InitializeComponent();
            init();
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void BuilderPatternsForm_Load(object sender, EventArgs e)
        {

        }
        /// <summary>
        /// 
        /// </summary>
        private void setPanel()
        {
            pnl.Location = new Point(152, 24);
            pnl.Size = new Size(128, 168);
            pnl.TabIndex = 1;
            Controls.Add(pnl);
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void lsEquities_SelectedIndexChanged(object sender, EventArgs e)
        {
            int i = lsEquities.SelectedIndex;
            Equities eq = (Equities)lsEquities.Items[i];
            mchoice = StockFactory.getBuilder(eq);
            this.Controls.Remove(pnl);
            pnl = mchoice.getWindow();
            setPanel();
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void btPlot_Click(object sender, EventArgs e)
        {
            //display the selected items in a message box
            if (mchoice != null)
            {
                ArrayList ar = mchoice.getSelected();
                string ans = "";
                for (int i = 0; i < ar.Count; i++)
                {
                    ans += (string)ar[i] + " ";
                }
                MessageBox.Show(null, ans, "Selected equities", MessageBoxButtons.OK);
            }
        }
    }

输出：