Using an ArrayList instead of an array (C#) : ArrayList « Collections « ASP.NET Tutorial





<%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!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 runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    
    </div>
    </form>
</body>
</html>

File: Default.aspx.cs

using System;
using System.Collections;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        Person scott = new Person("A", "B");
        Person bill = new Person("C", "D");
        Person srini = new Person("E", "F");

        ArrayList people = new ArrayList();
        people.Add(scott);
        people.Add(bill);
        people.Add(srini);

        Response.Write("We used foreach.<BR/>");
        foreach (Person p in people)
        {
            Response.Write(p.FullName + "<BR/>");
        }

        Response.Write("Sort...<BR/>");
        people.Sort();

        Response.Write("We used foreach.<BR/>");
        foreach (Person p in people)
        {
            Response.Write(p.FullName + "<BR/>");
        }

        Person scott2 = new Person("A", "B");
        int indexOfA2 = people.IndexOf(scott2);
        Response.Write("A #2 is at " + indexOfA2 + "<BR/>");

        int indexOfEquivalentA = people.BinarySearch(scott2);
        Response.Write("An Equivalent A is at " + indexOfEquivalentA +
        "<BR/>");

        Response.Write("We used a for loop.<BR/>");
        for (int i = 0; i < people.Count; i++)
        {
            Response.Write(((Person)people[i]).FullName + "<BR/>");
        }
    }
}

public class Person : IComparable
{
    string FirstName;
    string LastName;

    public Person(string first, string last)
    {
        FirstName = first;
        LastName = last;
    }

    public string FullName
    {
        get
        {
            return FirstName + " " + LastName;
        }
    }

    int IComparable.CompareTo(object obj)
    {
        Person p2 = obj as Person;
        if (p2 == null) throw new ArgumentException("Object is not a Person!");

        int lastNameResult = this.LastName.CompareTo(p2.LastName);

        if (lastNameResult == 0)
        {
            int firstNameResult = this.FirstName.CompareTo(p2.FirstName);
            return firstNameResult;
        }
        else
        {
            return lastNameResult;
        }
    }

}










7.2.ArrayList
7.2.1.Add objects to ArrayList (C#)
7.2.2.Add objects to ArrayList (VB)
7.2.3.Foreach loop (C#)
7.2.4.Foreach loop (VB)
7.2.5.Using an ArrayList instead of an array (C#)
7.2.6.Using an ArrayList instead of an array (VB)
7.2.7.Using a custom strongly typed PersonList (C#)
7.2.8.Using a custom strongly typed PersonList (VB)
7.2.9.ArrayList with custom objects
7.2.10.Bind ArrayList to DropDownList