Csharp/C Sharp/Collections Data Structure/ArrayList

Add array to ArrayList

using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
class Program {
    static void Main(string[] args) {
        ArrayList baseballTeams = new ArrayList();
        baseballTeams.Add("S");
        baseballTeams.Add("r");
        baseballTeams.Add("F");
        string[] myStringArray = new string[2];
        myStringArray[0] = "G";
        myStringArray[1] = "L";
        baseballTeams.AddRange(myStringArray);
        foreach (string item in baseballTeams) {
            Console.Write(item + "\n");
        }
    }
}

Add items to ArrayList and use foreach loop to check

using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
class Program {
    static void Main(string[] args) {
        ArrayList baseballTeams = new ArrayList();
        baseballTeams.Add("s");
        baseballTeams.Add("r");
        baseballTeams.Add("F");
        foreach (string item in baseballTeams) {
            Console.Write(item + "\n");
        }
    }
}

ArrayList Demo: hold class

/*
Learning C# 
by Jesse Liberty
Publisher: O"Reilly 
ISBN: 0596003765
*/
 using System;
 using System.Collections;
 namespace ArrayListDemo
 {
     // a class to hold in the array list
     class Employee
     {
         private int empID;
         public Employee(int empID)
         {
             this.empID = empID;
         }
         public override  string ToString()
         {
             return empID.ToString();
         }
         public int EmpID
         {
             get { return empID; }
             set { empID = value; }
         }
     }
     public class ArrayListDemoTester
     {
         public void Run()
         {
             ArrayList empArray = new ArrayList();
             ArrayList intArray = new ArrayList();
             // populate the arraylists
             for (int i = 0;i<5;i++)
             {
                 empArray.Add(new Employee(i+100));
                 intArray.Add(i*5);
             }
             // print each member of the array
             foreach (int i in intArray)
             {
                 Console.Write("{0} ", i.ToString());
             }
             Console.WriteLine("\n");
             // print each employee
             foreach(Employee e in empArray)
             {
                 Console.Write("{0} ", e.ToString());
             }
             Console.WriteLine("\n");
             Console.WriteLine("empArray.Capacity: {0}",
                 empArray.Capacity);
         }
         [STAThread]
         static void Main()
         {
             ArrayListDemoTester t = new ArrayListDemoTester();
             t.Run();
         }
     }
 }

Binary Search an ArrayList

using System;
using System.Collections;
class Album : IComparable, ICloneable {
    private string _Title;
    private string _Artist;
    public Album(string artist, string title) {
        _Artist = artist;
        _Title = title;
    }
    public string Title {
        get {
            return _Title;
        }
        set {
            _Title = value;
        }
    }
    public string Artist {
        get {
            return _Artist;
        }
        set {
            _Artist = value;
        }
    }
    public override string ToString() {
        return _Artist + ",\t" + _Title;
    }
    public int CompareTo(object o) {
        Album other = o as Album;
        if (other == null)
            throw new ArgumentException();
        if (_Artist != other._Artist)
            return _Artist.rupareTo(other._Artist);
        else
            return _Title.rupareTo(other._Title);
    }
    public object Clone() {
        return new Album(_Artist, _Title);
    }
}
class TitleComparer : IComparer {
    public int Compare(object l, object r) {
        Album left = l as Album;
        Album right = r as Album;
        if ((left == null) || (right == null))
            throw new ArgumentException();
        if (left.Title != right.Title)
            return left.Title.rupareTo(right.Title);
        else
            return left.Artist.rupareTo(right.Artist);
    }
}
class Class1 {
    static void Main(string[] args) {
        ArrayList arr = new ArrayList();
        arr.Add(new Album("G", "A"));
        arr.Add(new Album("B", "G"));
        arr.Add(new Album("S", "A"));
        arr.Sort();
   
        try {
            foreach (Album a in arr) {
                Console.WriteLine(a);
            }
        } catch (System.InvalidCastException e) {
        }
        arr.Sort(new TitleComparer());
        foreach (Album a in arr) {
            Console.WriteLine(a);
        }
        Album l = new Album("L", "G");
        arr.Sort();
        int index = arr.BinarySearch(l);
        Console.WriteLine(index.ToString());
        arr.Sort(new TitleComparer());
        index = arr.BinarySearch(l, new TitleComparer());
        Console.WriteLine(index.ToString());
    }
}

Check InvalidCastException when using foreach loop with ArrayList

using System;
using System.Collections;
class Album : IComparable, ICloneable {
    private string _Title;
    private string _Artist;
    public Album(string artist, string title) {
        _Artist = artist;
        _Title = title;
    }
    public string Title {
        get {
            return _Title;
        }
        set {
            _Title = value;
        }
    }
    public string Artist {
        get {
            return _Artist;
        }
        set {
            _Artist = value;
        }
    }
    public override string ToString() {
        return _Artist + ",\t" + _Title;
    }
    public int CompareTo(object o) {
        Album other = o as Album;
        if (other == null)
            throw new ArgumentException();
        if (_Artist != other._Artist)
            return _Artist.rupareTo(other._Artist);
        else
            return _Title.rupareTo(other._Title);
    }
    public object Clone() {
        return new Album(_Artist, _Title);
    }
}
public class foo {
    public foo() {
        myString = "Test";
    }
    private string myString;
}
class MainClass {
    static void Main(string[] args) {
        ArrayList arr = new ArrayList();
        arr.Add(new Album("G", "A"));
        arr.Add(new Album("B", "G"));
        arr.Add(new Album("S", "A"));
        arr.Sort();
        arr.Insert(0, new foo());
        try {
            foreach (Album a in arr) {
                Console.WriteLine(a);
            }
        } catch (System.InvalidCastException e) {
        }
    }
}

Checks time needed for list operations using an ArrayList implementation

using System;
using System.Drawing;
using System.Collections;
public class ArrayListTiming {
  public static void Main() {
    ArrayList arrayImp = new ArrayList();
    Point p = new Point(34, 156);
    int time1, time2;
    Object o;
    time1 = Environment.TickCount;
    for(int i = 0; i < 100000; i++)
       arrayImp.Add(p);
    time2 = Environment.TickCount;
    Console.WriteLine("Time for 100,000 adds: " + (time2 - time1));
    time1 = Environment.TickCount;
    for(int i = 0; i < 1000; i++)
       arrayImp.Insert(50, p);
    time2 = Environment.TickCount;
    Console.WriteLine("Time for 1,000 adds at position 50: " + (time2 - time1));
    time1 = Environment.TickCount;
    for(int i = 0; i < 10000000; i++)
       o = arrayImp[50];
    time2 = Environment.TickCount;
    Console.WriteLine ("Time for 10,000,000 gets at position 50: " + (time2 - time1));
  }
}

Clone an ArrayList

using System;
using System.Collections;
public class Starter {
    public static void Main(string[] argv) {
        ArrayList al1 = new ArrayList();
        foreach (string arg in argv) {
            al1.Add(int.Parse(arg));
        }
        al1.Sort();
        ArrayList al2 = (ArrayList)al1.Clone();
        for (int count = 0; count < al2.Count; ++count) {
            al2[count] = ((int)al2[count]) * 2;
        }
        foreach (int number in al2) {
            Console.WriteLine(number);
        }
    }
}

Convert an ArrayList into an array

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Convert an ArrayList into an array. 
 
using System; 
using System.Collections; 
 
public class ArrayListToArray { 
  public static void Main() { 
    ArrayList al = new ArrayList(); 
     
    // Add elements to the array list. 
    al.Add(1); 
    al.Add(2); 
    al.Add(3); 
    al.Add(4); 
 
    Console.Write("Contents: "); 
    foreach(int i in al) 
      Console.Write(i + " "); 
    Console.WriteLine(); 
 
    // Get the array. 
    int[] ia = (int[]) al.ToArray(typeof(int)); 
    int sum = 0; 
 
    // sum the array 
    for(int i=0; i<ia.Length; i++) 
      sum += ia[i]; 
 
    Console.WriteLine("Sum is: " + sum); 
  } 
}

CopyTo, ToArray(), ToArray(typeof(String))

 

using System; 
using System.Collections;
    class MainClass
    {
        public static void Main()
        {
            ArrayList list = new ArrayList(5);
            list.Add("B");
            list.Add("G");
            list.Add("J");
            list.Add("S");
            list.Add("M");
            string[] array1 = new string[list.Count];
            list.CopyTo(array1, 0);

            object[] array2 = list.ToArray();
            string[] array3 = (string[])list.ToArray(typeof(String));
            
            foreach (string s in array1)
            {
                Console.WriteLine(s);
            }
            foreach (string s in array2)
            {
                Console.WriteLine(s);
            }
            foreach (string s in array3)
            {
                Console.WriteLine(s);
            }
         }
    }

Demonstrate ArrayList

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Demonstrate ArrayList. 
 
using System; 
using System.Collections; 
 
public class ArrayListDemo { 
  public static void Main() { 
    // create an array list 
    ArrayList al = new ArrayList(); 
     
    Console.WriteLine("Initial capacity: " + 
                       al.Capacity); 
    Console.WriteLine("Initial number of elements: " + 
                       al.Count); 
 
    Console.WriteLine(); 
 
    Console.WriteLine("Adding 6 elements"); 
    // Add elements to the array list 
    al.Add("C"); 
    al.Add("A"); 
    al.Add("E"); 
    al.Add("B"); 
    al.Add("D"); 
    al.Add("F"); 
 
    Console.WriteLine("Current capacity: " + 
                       al.Capacity); 
    Console.WriteLine("Number of elements: " + 
                       al.Count); 
 
    // Display the array list using array indexing. 
    Console.Write("Current contents: "); 
    for(int i=0; i < al.Count; i++) 
      Console.Write(al[i] + " "); 
    Console.WriteLine("\n"); 
 
    Console.WriteLine("Removing 2 elements"); 
    // Remove elements from the array list. 
    al.Remove("F"); 
    al.Remove("A"); 
 
    Console.WriteLine("Current capacity: " + 
                       al.Capacity); 
    Console.WriteLine("Number of elements: " + 
                       al.Count); 
 
    // Use foreach loop to display the list. 
    Console.Write("Contents: "); 
    foreach(char c in al) 
      Console.Write(c + " "); 
    Console.WriteLine("\n"); 
 
    Console.WriteLine("Adding 20 more elements"); 
    // Add enough elements to force al to grow. 
    for(int i=0; i < 20; i++) 
      al.Add((char)("a" + i)); 
    Console.WriteLine("Current capacity: " + 
                       al.Capacity); 
    Console.WriteLine("Number of elements after adding 20: " + 
                       al.Count); 
    Console.Write("Contents: "); 
    foreach(char c in al) 
      Console.Write(c + " "); 
    Console.WriteLine("\n"); 
 
    // Change contents using array indexing. 
    Console.WriteLine("Change first three elements"); 
    al[0] = "X"; 
    al[1] = "Y"; 
    al[2] = "Z"; 
    Console.Write("Contents: "); 
    foreach(char c in al) 
      Console.Write(c + " "); 
    Console.WriteLine(); 
  } 
}

illustrates the use of an ArrayList that contains objects of the Car class

/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
  Example11_3.cs illustrates the use of an ArrayList that contains
  objects of the Car class
*/
using System;
using System.Collections;

// declare the Car class
class Car : IComparable
{
  // declare the fields
  public string model;
  public int yearBuilt;
  // define the constructor
  public Car(string model, int yearBuilt)
  {
    this.model = model;
    this.yearBuilt = yearBuilt;
  }
  // override the ToString() method
  public override string ToString()
  {
    return "model is " + model + ", yearBuilt is " + yearBuilt;
  }
  // implement the Compare() method of IComparer
  public int Compare(object lhs, object rhs)
  {
    Car lhsCar = (Car) lhs;
    Car rhsCar = (Car) rhs;
    if (lhsCar.yearBuilt < rhsCar.yearBuilt)
    {
      return -1;
    }
    else if (lhsCar.yearBuilt > rhsCar.yearBuilt)
    {
      return 1;
    }
    else
    {
      return 0;
    }
  }
  // implement the CompareTo() method of IComparable
  public int CompareTo(object rhs)
  {
    return Compare(this, rhs);
  }
  // alternative CompareTo() method that simply calls the
  // CompareTo() method that comes with the int type
  // (currently commented out)
  /* public int CompareTo(object rhs)
  {
    Car rhsCar = (Car) rhs;
    return this.yearBuilt.rupareTo(rhsCar.yearBuilt);
  }*/
}

public class Example11_3
{
  // the DisplayArrayList() method displays the elements in the
  // supplied ArrayList
  public static void DisplayArrayList(
    string arrayListName, ArrayList myArrayList
  )
  {
    for (int counter = 0; counter < myArrayList.Count; counter++)
    {
      Console.WriteLine(arrayListName + "[" + counter + "] = " +
        myArrayList[counter]);
    }
  }
  public static void Main()
  {
    // create an ArrayList object
    ArrayList myArrayList = new ArrayList();
    // add four Car objects to myArrayList using the Add() method
    Console.WriteLine("Adding four Car objects to myArrayList");
    Car myMR2 = new Car("MR2", 2001);
    Car myBoxster = new Car("Boxster", 2001);
    Car myCorvette = new Car("Corvette", 1999);
    Car myThunderbird = new Car("Thunderbird", 1979);
    myArrayList.Add(myMR2);
    myArrayList.Add(myBoxster);
    myArrayList.Add(myCorvette);
    myArrayList.Add(myThunderbird);
    DisplayArrayList("myArrayList", myArrayList);
    // use the Contains() method to determine if myBoxster
    // is in the ArrayList; if it is, then use the IndexOf()
    // method to display the index
    if (myArrayList.Contains(myBoxster))
    {
      Console.WriteLine("myArrayList does contain myBoxster");
      int index = myArrayList.IndexOf(myBoxster);
      Console.WriteLine("myBoxster occurs at index " + index);
    }
    // remove myBoxster from myArrayList
    Console.WriteLine("Removing myBoxster from myArrayList");
    myArrayList.Remove(myBoxster);
    DisplayArrayList("myArrayList", myArrayList);
    // use the Sort() method to sort myArrayList
    Console.WriteLine("Using the Sort() method to sort myArrayList");
    myArrayList.Sort();
    DisplayArrayList("myArrayList", myArrayList);
    // use the BinarySearch() method to search myArrayList for
    // myCorvette
    Console.WriteLine("Using the BinarySearch() method to search myArrayList\n" +
      " for myCorvette");
    int index2 = myArrayList.BinarySearch(myCorvette);
    Console.WriteLine("Found myCorvette at index " + index2);
    // use the GetRange() method to get a range of elements
    // from myArrayList
    Console.WriteLine("Using the GetRange() method to get two\n" +
      " elements from myArrayList, starting at index 1");
    ArrayList anotherArrayList = myArrayList.GetRange(1, 2);
    DisplayArrayList("anotherArrayList", anotherArrayList);
    // get an enumerator using the GetEnumerator() method
    // and use it to read the elements in myArrayList
    Console.WriteLine("Using the GetEnumerator() method to get an enumerator");
    IEnumerator myEnumerator = myArrayList.GetEnumerator();
    while (myEnumerator.MoveNext())
    {
      Console.WriteLine("myEnumerator.Current = " + myEnumerator.Current);
    }
    // use the Reset() method and access the first row again using MoveNext()
    Console.WriteLine("Using the Reset() method and accessing\n" +
      " the first row again using MoveNext()");
    myEnumerator.Reset();
    myEnumerator.MoveNext();
    Console.WriteLine("myEnumerator.Current = " + myEnumerator.Current);
    // Use a foreach statement to read the contents of myArrayList
    Console.WriteLine("Using a foreach statement to read the contents of myArrayList");
    foreach (Car myCar in myArrayList)
    {
      System.Console.WriteLine("myCar = " + myCar);
    }
  }
}

illustrates the use of ArrayList properties and methods

/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
  Example11_2.cs illustrates the use of ArrayList properties
  and methods
*/
using System;
using System.Collections;
public class Example11_2
{
  // the DisplayArrayList() method displays the elements in the
  // ArrayList that is supplied as a parameter
  public static void DisplayArrayList(
    string arrayListName, ArrayList myArrayList
  )
  {
    for (int counter = 0; counter < myArrayList.Count; counter++)
    {
      Console.WriteLine(arrayListName + "[" + counter + "] = " +
        myArrayList[counter]);
    }
  }
  public static void Main()
  {
    // create an ArrayList object
    ArrayList myArrayList = new ArrayList();
    // set and display the Capacity property
    myArrayList.Capacity = 10;
    Console.WriteLine("myArrayList.Capacity = " +
      myArrayList.Capacity);
    // display the IsFixedSize and IsReadOnly properties
    Console.WriteLine("myArrayList.IsFixedSize = " +
      myArrayList.IsFixedSize);
    Console.WriteLine("myArrayList.IsReadOnly = " +
      myArrayList.IsReadOnly);
    // add eight string elements to myArrayList using the Add(),
    // Insert(), AddRange(), and InsertRange() methods
    Console.WriteLine("Adding eight string elements to myArrayList");
    myArrayList.Add("This");
    myArrayList.Insert(1, "is");
    string[] myStringArray = {"a", "test"};
    myArrayList.AddRange(myStringArray);
    string[] anotherStringArray = {"Here"s", "some", "more", "text"};
    myArrayList.InsertRange(myArrayList.Count, anotherStringArray);
    // display the elements in myArrayList using the
    // DisplayArrayList() method defined earlier
    DisplayArrayList("myArrayList", myArrayList);
    // use the SetRange() method to copy the elements from
    // anotherStringArray to myArrayList, starting at index 0
    Console.WriteLine("Using the SetRange() method to copy the\n" +
      "elements from anotherStringArray to myArrayList,\n" +
      "starting at index 0");
    myArrayList.SetRange(0, anotherStringArray);
    DisplayArrayList("myArrayList", myArrayList);
    // use the Contains() method to determine if the string "text"
    // is in the ArrayList; if it is, then use the IndexOf() and
    // LastIndexOf() methods to display the first and last occurrence
    if (myArrayList.Contains("text"))
    {
      int index = myArrayList.IndexOf("text");
      Console.WriteLine("myArrayList does contain the word "text"");
      Console.WriteLine(""text" first occurs at index " + index);
      index = myArrayList.LastIndexOf("text");
      Console.WriteLine(""text" last occurs at index " + index);
    }
    // remove element 0, first "text" element, and two
    // elements starting at index 3
    Console.WriteLine("Removing elements from myArrayList");
    myArrayList.RemoveAt(0);
    myArrayList.Remove("text");
    myArrayList.RemoveRange(3, 2);
    DisplayArrayList("myArrayList", myArrayList);
    // use the Sort() method to sort myArrayList
    Console.WriteLine("Using the Sort() method to sort myArrayList");
    myArrayList.Sort();
    DisplayArrayList("myArrayList", myArrayList);
    // use the BinarySearch() method to search myArrayList
    Console.WriteLine("Using the BinarySearch() method to search myArrayList");
    int index2 = myArrayList.BinarySearch("some");
    Console.WriteLine("Found "some" at index " + index2);
    // use the Reverse() method to reverse myArrayList
    Console.WriteLine("Using the Reverse() method");
    myArrayList.Reverse();
    DisplayArrayList("myArrayList", myArrayList);
    // use the TrimToSize() method to reduce the capacity of
    // myArrayList to the actual number of elements in myArrayList
    Console.WriteLine("Using the TrimToSize() method to reduce the\n" +
      "capacity of myArrayList");
    myArrayList.TrimToSize();
    Console.WriteLine("myArrayList.Capacity = " +
      myArrayList.Capacity);
    // use the GetRange() method to get a range of elements
    // from myArrayList
    Console.WriteLine("Using the GetRange() method to get two\n" +
      "elements from myArrayList, starting at index 1");
    ArrayList anotherArrayList = myArrayList.GetRange(1, 2);
    DisplayArrayList("anotherArrayList", anotherArrayList);
    // get an enumerator using the GetEnumerator() method
    // and use it to read the elements in myArrayList
    Console.WriteLine("Using the GetEnumerator() method to get an enumerator");
    IEnumerator myEnumerator = myArrayList.GetEnumerator();
    while (myEnumerator.MoveNext())
    {
      Console.WriteLine("myEnumerator.Current = " + myEnumerator.Current);
    }
    // use the Reset() method and access the first row again using MoveNext()
    Console.WriteLine("Using the Reset() method and accessing\n" +
      " the first row again using MoveNext()");
    myEnumerator.Reset();
    myEnumerator.MoveNext();
    Console.WriteLine("myEnumerator.Current = " + myEnumerator.Current);
    // Use a foreach statement to read the contents of myArrayList
    Console.WriteLine("Using a foreach statement to read the contents of myArrayList");
    foreach (string myString in myArrayList)
    {
      System.Console.WriteLine("myString = " + myString);
    }
  }
}

illustrates the use of ArrayLists 2

/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
  Example11_1.cs illustrates the use of ArrayLists
*/
using System;
using System.Collections;
public class Example11_1
{
  // the DisplayArrayList() method displays the elements in the
  // ArrayList that is supplied as a parameter
  public static void DisplayArrayList(
    string arrayListName, ArrayList myArrayList
  )
  {
    for (int counter = 0; counter < myArrayList.Count; counter++)
    {
      Console.WriteLine(arrayListName + "[" + counter + "] = " +
        myArrayList[counter]);
    }
  }
  public static void Main()
  {
    // create an ArrayList object
    ArrayList myArrayList = new ArrayList();
    // display the Capacity property
    Console.WriteLine("myArrayList.Capacity = " +
      myArrayList.Capacity);
    // add four strings to myArrayList using the Add() method
    myArrayList.Add("This");
    myArrayList.Add("is");
    myArrayList.Add("a");
    myArrayList.Add("test");
    // display the contents of myArrayList using DisplayArrayList()
    DisplayArrayList("myArrayList", myArrayList);
    // create another ArrayList, passing myArrayList to the
    // constructor of the new ArrayList
    ArrayList anotherArrayList = new ArrayList(myArrayList);
    // display the contents of anotherArrayList
    DisplayArrayList("anotherArrayList", anotherArrayList);
  }
}

Inserting into an ArrayList by index

using System;
using System.Collections;
class MainClass {
    public static void Main() {
        ArrayList al = new ArrayList(5);
        // Add three elements to the end of the array
        al.Add(10);
        al.Add(9);
        al.Add(8);
        // Now, insert three elements in the front of the array
        al.Insert(0, 1);
        al.Insert(0, 2);
        al.Insert(0, 3);
        // Finally, insert into some random spots
        al.Insert(2, 4);
        al.Insert(4, 5);
        al.Insert(6, 6);

        // Enumerate the array
        foreach (int i in al) {
            Console.WriteLine("Entry {0}", i);
        }
    }
}

Remove range from ArrayList

using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
class Program {
    static void Main(string[] args) {
        ArrayList baseballTeams = new ArrayList();
        baseballTeams.Add("s");
        baseballTeams.Add("r");
        baseballTeams.Add("i");
        string[] myStringArray = new string[2];
        myStringArray[0] = "t";
        myStringArray[1] = "L";
        baseballTeams.AddRange(myStringArray);
        baseballTeams.RemoveRange(2, 2);
        foreach (string item in baseballTeams) {
            Console.Write(item + "\n");
        }
        Console.ReadLine();
    }
}

Sort and search an ArrayList

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Sort and search an ArrayList. 
 
using System; 
using System.Collections; 
 
public class SortSearchDemo { 
  public static void Main() { 
    // create an array list 
    ArrayList al = new ArrayList(); 
     
    // Add elements to the array list 
    al.Add(55); 
    al.Add(43); 
    al.Add(-4); 
    al.Add(88); 
    al.Add(3); 
    al.Add(19); 
 
    Console.Write("Original contents: "); 
    foreach(int i in al) 
      Console.Write(i + " "); 
    Console.WriteLine("\n"); 
 
    // Sort 
    al.Sort(); 
 
    // Use foreach loop to display the list. 
    Console.Write("Contents after sorting: "); 
    foreach(int i in al) 
      Console.Write(i + " "); 
    Console.WriteLine("\n"); 
 
    Console.WriteLine("Index of 43 is " + 
                      al.BinarySearch(43)); 
  } 
}

Using foreach to loop through ArrayList and use Indexer of ArrayList

 
using System;
using System.Collections;
class CollectionsDemo {
    public static void Main(String[] args) {
        ArrayList PokerPlayers = new ArrayList(3);
        PokerPlayers.Add("J");
        PokerPlayers.Add("M");
        PokerPlayers.Add("A");
        PokerPlayers.Add("J");
        foreach (String Player in PokerPlayers) {
            Console.WriteLine(Player);
        }
        PokerPlayers[0] = "A";
        System.Console.WriteLine(PokerPlayers[0]);
    }
}