Csharp/CSharp Tutorial/Data Structure/ReadOnlyCollectionBase

extends ReadOnlyCollectionBase

using System;
using System.Drawing;
using System.Collections;
using System.ruponentModel;
using System.Windows.Forms;
using System.Data;
  public class MainClass
  {
    static void Main() 
    {
          Customers customers = new Customers();
          foreach(Customer c in customers)
          {
            System.Console.WriteLine(c.Name + ", " + c.Phone);
          }
        }
  }
  
  public class Customers : ReadOnlyCollectionBase
  {
        public Customers()
        {
          ReadCustomers();
        }
    
        public Customer this[int index]
        {
          get
          {
            return (Customer)InnerList[index];
          }
        }
        
        
        public Customer this[string name]
        {
          get
          {
            return (Customer)this[Find(name)];
          }
        }
        
        private int Find(string name)
        {
          for( int i = 0; i < Count - 1; i++)
          {
            if( this[i].Name.Equals(name) ) return i;
          }
          return -1;
        }
        
        private void ReadCustomers()
        {
          InnerList.Add( new Customer("A", "(666) 555-1212"));
          InnerList.Add( new Customer("M", "(503) 555-1212"));
        }
      }
      
      public class Customer
      {
       
            public Customer(string name, string phone)
            {
              this.Name = name;
              this.Phone = phone;
            }    
      
        public string Name;
        
        public string Phone;
       }