Finding Duplicate Elements in Array [C# Code]

You might searched a lot on internet for finding duplicate elements in an array but not succeded with correct one. Here I am going to explain with code o=how you can determine if an array contains duplicate elements.It might helps you.

Here I have taken a fixed length array with hardcoded values.
You can use your own array which is being returned from another methods etc.
Creatd a Button,on click of button I am calling a method which returns true or false and Showing the same to the user through messagebox.
Do reply if you have some problem in running this code.

using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;
public class Form1

static int[] numbers = {1,2,3,1,5};

private void Button1_Click(System.Object sender, System.EventArgs e)
bool duplicates = false;

duplicates = IsArrayDuplicated(numbers);



private static bool IsArrayDuplicated(int[] numbers)

bool result = false;

int n = 0;

int n1 = 0;

int i = 0;

result = false;

//Dim bits As New BitArray(numbers.Length + 1)

for (n = i; n <= numbers.Length - 1; n++) {

for (n1 = i + 1; n1 <= numbers.Length - 1; n1++) {

if (numbers[n] == numbers[n1] & n != n1) {
result = true;


} else {




return result;



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