How to Shuffle a List in C# - Step by Step Examples

How to Shuffle a List in C# ?

Answer

To shuffle a list in C#, you can use the OrderBy method with a random key selector or implement a custom shuffle method using the Fisher-Yates algorithm.

✐ Examples

1 Shuffle a List Using the OrderBy Method

In this example,

We create a list named numbers with integer values.
We use the OrderBy method with a random key selector to shuffle the list.
The OrderBy method sorts the elements based on random keys generated by Guid.NewGuid().
Finally, we print the shuffled list to standard output.

C# Program

using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main()
    {
        List<int> numbers = new List<int> { 1, 2, 3, 4, 5 };
        List<int> shuffledNumbers = numbers.OrderBy(x => Guid.NewGuid()).ToList();
        Console.WriteLine("Shuffled list: " + string.Join(", ", shuffledNumbers));
    }
}

Output

Shuffled list: 3, 1, 5, 4, 2

2 Shuffle a List Using the Fisher-Yates Algorithm

In this example,

We create a list named numbers with integer values.
We implement a custom method called ShuffleList that takes a list as input.
Inside ShuffleList, we use a random number generator to swap each element with a random element that comes after it, iterating from the end of the list to the start.
The outer loop iterates from the last element to the second element, and the inner loop performs the element swap.
Finally, we print the shuffled list to standard output.

C# Program

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        List<int> numbers = new List<int> { 1, 2, 3, 4, 5 };
        ShuffleList(numbers);
        Console.WriteLine("Shuffled list: " + string.Join(", ", numbers));
    }

    static void ShuffleList(List<int> list)
    {
        Random rng = new Random();
        int n = list.Count;
        for (int i = n - 1; i > 0; i--)
        {
            int j = rng.Next(i + 1);
            int temp = list[i];
            list[i] = list[j];
            list[j] = temp;
        }
    }
}

Output

Shuffled list: 4, 1, 5, 2, 3

Summary

In this tutorial, we learned How to Shuffle a List in C# language with well detailed examples.

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How to Shuffle a List in C# - Step by Step Examples

How to Shuffle a List in C# ?

Answer

✐ Examples

1 Shuffle a List Using the OrderBy Method

C# Program

Output

2 Shuffle a List Using the Fisher-Yates Algorithm

C# Program

Output

Summary

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