c# list get element by index code example

Example 1: c# find index element array

int[] arr = { 3, 6, 4, 1, 6, 8 };

// returns 1
Array.IndexOf(arr, 6);

Example 2: c# list index

// Get the first item from the list

using System.Linq;

var myList = new List<string>{ "Yes", "No", "Maybe"};
var firstItem = myList.ElementAt(0);

// Do something with firstItem

Example 3: c# get index of item in list

Array.IndexOf(arrName, searchingFor)

Example 4: find index of string in a list C#

using System;
using System.Collections.Generic;
public class Program {
   public static void Main() {
      List < string > myList = new List < string > () {
         "Football",
         "Soccer",
         "Tennis",
      };

      // finding index
      int index = myList.FindIndex(a => a.Contains("Tennis"));

      // displaying index
      Console.WriteLine("List Item Tennis Found at index: " + index);
   }
}

Example 5: get both item and index in c#

// add this to your namespace
public static IEnumerable<(T item, int index)> WithIndex<T>(this IEnumerable<T> source)
{
    return source.Select((item, index) => (item, index));
}

//do something like this

foreach (var (item, index) in collection.WithIndex())
{
    DoSomething(item, index);
}