Hashtable collection : Hashtable « Collections « ASP.NET Tutorial






  1. ASP.NET Tutorial
  2. Collections
  3. Hashtable
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="UsingHashtable" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Hashtable Example</title>
</head>
<body>
    <form id="form1" runat="server">
   <div id="container">
      <h1>Hashtable Example</h1>
      
      <asp:ListBox ID="lboxCustomers" runat="server" 
         DataTextField="Value"
         DataValueField="Key" />   
         
   </div>
    </form>
</body>
</html>

File: Default.aspx.cs

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public abstract class AbstractEntity
{

   private string _id;

  public AbstractEntity(string id)
  {
      _id = id;
  }


   public string Id
   {
      get { return _id; }
      set { _id = value; }
   }


   public abstract bool IsValid
   {
      get;
   }
}

public class Customer: AbstractEntity 
{
   // data members
   private string _firstName;
   private string _lastName;
   private string _phone;

   public Customer(string id, string firstName, string lastName, string phone): base(id)
   {
      _firstName = firstName;
      _lastName = lastName;
      _phone = phone;
   }


   public string FirstName
   {
      get { return _firstName; }
      set { _firstName = value; }
   }
   public string LastName
   {
      get { return _lastName; }
      set { _lastName = value; }
   }
   public string Phone
   {
      get { return _phone; }
      set { _phone = value; }
   }
   public string Name
   {
      get { return LastName + ", " + FirstName; }
   }

   public override bool IsValid
   {
      get
      {
         if (Id.Length > 0 && LastName.Length > 0)
            return true;
         else
            return false;
      }
   }

   public override string ToString()
   {
      return Id + "," + Name + "," + Phone; 
   }
}

public partial class UsingHashtable : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
       Customer c1 = new Customer("1", "A", "AA", "123-4567");
       Customer c2 = new Customer("2", "B", "BB", "123-7823");
       Customer c3 = new Customer("3", "C", "CC", "123-6383");

       Hashtable table = new Hashtable();
       table.Add(c1.Id, c1);
       table.Add(c2.Id, c2);
       table.Add(c3.Id, c3);

       lboxCustomers.DataSource = table;
       lboxCustomers.DataBind();
    }
}








7.5.Hashtable
7.5.1.Hashtable collection
7.5.2.Retrieving Person objects from a Hashtable (C#)
7.5.3.Retrieving Person objects from a Hashtable (VB)
7.5.4.Using For Each with a Hashtable's default IEnumerator implementation (C#)
7.5.5.Using For Each with a Hashtable's default IEnumerator implementation (VB)
7.5.6.Using For Each with a Hashtable's Keys and Values member collections (C#)
7.5.7.Using For Each with a Hashtable's Keys and Values member collections (VB)