Search for the specified object and returns the zero-based index of the first occurrence within the entire Collection in CSharp

using System;//  w w  w  .jav  a2 s.c o m
using System.Collections.Generic;
using System.Collections.ObjectModel;

public class Demo
{
    public static void Main()
    {
        Collection<string> myData = new Collection<string>();

        myData.Add("A");
        myData.Add("B");
        myData.Add("C");
        myData.Add("D");
 
        foreach( string item in myData)
        {
            Console.WriteLine(item);
        }     
 
        Console.WriteLine(myData.IndexOf("D"));

    }
}