Array List:-

• The  Array List  class  is  a  dynamic  array  of heterogeneous  objects.

• If  we  create  an array  of object type , then it is possible  to  store  items  of  different  types.
• An  Arraylist use its indexes  to  refer  to  a  particular  item stored  in  its  collection.
• Declaring  an ArrayList:-
• ArrayList  objArrList=new  ArrayList();

       Example:-

• Add Items in ArrayList collection in console application

whenever  we will used  the ArrayList  we need to import  one namespace i.e.,”System.Collections”

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Collections;// import this namespace namespace CAArrayList {     class ClsArrayList     {         static void Main(string[] args)         {             ArrayList objArrList = new ArrayList();             //Add Items to the ArrayList collection             objArrList.Add("Sampath");             objArrList.Add("kumar");             objArrList.Add("vaddepally");             foreach (Object objItem in objArrList)             {                 Console.WriteLine(objItem);             }             Console.Write("Enter a value to Add:");             object objValue = Console.ReadLine();             objArrList.Add(objValue);             Console.WriteLine("---------After adding value---------\n Array    list Elements Are");             foreach (Object objItem in objArrList)             {                 Console.WriteLine(objItem);             }             Console.Read();         }     } }

Output:-

Differences between Array & ArrayList

SNO	Array	Array List
1	int[ ] A=new int[ ]{1,4,3};	ArrayList objArrayList=new  ArrayList();
2	Array is in the System namespace	ArrayList is in the System. Collections namespace
3	The capacity of an Array is fixed	ArrayList can increase and decrease size dynamically
4	Array is a collection of similar items	An Array is a collection of similar items
5	Array can  have multiple dimensions	ArrayList always has exactly one dimension