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

1 Answers

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