System.Linq.Last - .NET API Documentation

Method: Last<TSource>

Returns the last element of a sequence.

Declaration

public static TSource Last<TSource>(this IEnumerable<TSource> source);

Parameters

source: An IEnumerable<TSource> to return the last element from. This parameter is required.

Return Value

TSource: The last element of the sequence.

Exceptions

ArgumentNullException: source is null.
InvalidOperationException: The sequence is empty.

Remarks

The Last method returns the last element of a sequence. This method is an implementation of the IQueryable<T> Last extension method. For IEnumerable<T> sources, the last element is returned. If the sequence is empty, an InvalidOperationException is thrown.

This method iterates through the sequence. If the sequence is a list or an array, the last element can be accessed more efficiently by using the indexer.

Examples

Example 1: Getting the last element of an array

int[] numbers = { 5, 4, 3, 2, 1 };
int lastNumber = numbers.Last(); // lastNumber is 1

Console.WriteLine(lastNumber);

Example 2: Getting the last element of a list

List<string> names = new List<string> { "Alice", "Bob", "Charlie" };
string lastName = names.Last(); // lastName is "Charlie"

Console.WriteLine(lastName);

Example 3: Handling an empty sequence

List<int> emptyList = new List<int>();
try
{
    int element = emptyList.Last();
}
catch (InvalidOperationException ex)
{
    Console.WriteLine("The sequence is empty.");
    // Output: The sequence is empty.
}