How to remove duplicate values from an array in C#?

Question

Ravi Vishwakarma · Answer

You can implement custom logic to remove duplicates.and 
Here's an example:
using System;
using System.Collections.Generic;
using System.Linq;
namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            // Original array
            int[] array = { 1, 2, 3, 1, 2, 3, 1, 4, 74, 8, 5, 74, 85, 8, 2, 4, 5, 4, 2, 11, 25, 4455, 6, 9, 966, 65, 78, 8, 8, 95, 574, 12 };
            Console.WriteLine("Original Array Length : " + array.Length);
            // Get distinct array
            var DistinctArray = Program.DistinctArray(array);
            Console.WriteLine("Distinct Array Length : " + DistinctArray.Length);
            foreach (var item in DistinctArray)
            {
                Console.Write(item + ", ");
            }
            Console.WriteLine();
            //Print array as a string with comma seperate
            Console.WriteLine(string.Join(", ", DistinctArray));
            Console.ReadLine();
        }
        // Method to return distinct elements from an array
        public static int[] DistinctArray(int[] array)
        {
            IListandlt;int> list = new Listandlt;int>();
            foreach (var item in array)
            {
                // Add item to list if it's not already present
                if (!list.Contains(item))
                {
                    list.Add(item);
                }
            }
            return list.ToArray();
            /* 
             * You can also put code to remove duplicate items from array 
             * using LINQ:
             * return array.Distinct().ToArray();
             */
        }
    }
}
Output -
Let this ‘DistinctArray’ method convert into the generic methodand 
using System;
using System.Collections.Generic;
using System.Linq;
namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            // Original array
            Console.WriteLine("For Interger");
            int[] array = { 1, 2, 3, 1, 2, 3, 1, 4, 74, 8, 5, 74, 85, 8, 2, 4, 5, 4, 2, 11, 25, 4455, 6, 9, 966, 65, 78, 8, 8, 95, 574, 12 };
            Console.WriteLine("Original Array Length : " + array.Length);
            // Get distinct array
            var DistinctArray = Program.DistinctArrayandlt;int>(array);
            Console.WriteLine("Distinct Array Length : " + DistinctArray.Length);
            foreach (var item in DistinctArray)
            {
                Console.Write(item + ", ");
            }
            Console.WriteLine();
            //Print array as a string with comma seperate
            Console.WriteLine(string.Join(", ", DistinctArray));
            Console.WriteLine("----------------------------------------------------");
            //For string 
            Console.WriteLine("For String");
            // Original array
            string[] StringArray = { "a", "A", "a", "b", "B", "ram", "raM" , "ram"};
            Console.WriteLine("Original Array Length : " + StringArray.Length);
            // Get distinct array
            var StringDistinctArray = Program.DistinctArrayandlt;string>(StringArray);
            Console.WriteLine("Distinct Array Length : " + StringDistinctArray.Length);
            foreach (var item in StringDistinctArray)
            {
                Console.Write(item + ", ");
            }
            Console.WriteLine();
            //Print array as a string with comma seperate
            Console.WriteLine(string.Join(", ", StringDistinctArray));
            Console.ReadLine();
        }
        // Generic Method to return distinct elements from an any array
        public static T[] DistinctArrayandlt;T>(T[] array)
        {
            IListandlt;T> list = new Listandlt;T>();
            foreach (var item in array)
            {
                // Add item to list if it's not already present
                if (!list.Containsandlt;T>(item))
                {
                    list.Add(item);
                }
            }
            return list.ToArrayandlt;T>();
        }
    }
}
Output -
and 
Read Also -
How to get a comma separated string from an array in C#?
What is the difference between 'String' and 'string' in C#?
Foreach Loop in C#

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How to remove duplicate values from an array in C#?

Ravi Vishwakarma

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