Sort an array in descending order in C#

This post will discuss how to sort an array in descending order in C#.

1. Using `Array.Sort` method

The standard solution to in-place sort an array in C# is using the Array.Sort() method. It takes a comparator to compare two elements and determine which element should appear first in the final sorted array. For sorting in descending order, we can provide a custom comparison function that reverses the default sort order.

using System;

public class Example

{

public static void Main()

{

int[] array = new int[] { 5, 7, 2, 3, 9 };

Array.Sort(array, (x, y) => y.CompareTo(x));

Console.WriteLine(String.Join(", ", array)); // 9, 7, 5, 3, 2

}

Download Run Code

The above solution uses a lambda expression to create an anonymous function. In older versions of C#, consider using the anonymous method feature of C# with Action<T> delegate.

using System;

public class Example

{

public static void Main()

{

int[] array = new int[] { 5, 7, 2, 3, 9 };

Array.Sort(array, delegate(int x, int y) {

return y - x;

});

Console.WriteLine(String.Join(", ", array)); // 9, 7, 5, 3, 2

}

Download Run Code

2. Using `Enumerable.OrderByDescending` method

The LINQ’s Enumerable.OrderByDescending method sorts elements of a sequence in descending order. This method avoids modifications to the original array and returns a new sorted array instead according to the specified comparator. This is the preferred method for out-of-place sorting in C#.

using System;

using System.Linq;

public class Example

{

public static void Main()

{

int[] array = new int[] { 5, 7, 2, 3, 9 };

int[] reversedSorted = array.OrderByDescending(x => x).ToArray();

Console.WriteLine(String.Join(", ", reversedSorted)); // 9, 7, 5, 3, 2

}

Download Run Code

That’s all about sorting an array in descending order in C#.

Sort an array in descending order in C#

1. Using Array.Sort method

2. Using Enumerable.OrderByDescending method

Share this:

1. Using `Array.Sort` method

2. Using `Enumerable.OrderByDescending` method