How to concatenate two arrays in C#

we are going to learn about how to concatenate the two arrays in C# with the help of examples.

Concatenation means the joining of two or more arrays into a single array.

Consider, we have the following two arrays:

int[] array1 = { 1, 2, 3 };int[] array2 = { 4, 5, 6 };

Now, we need to join above two arrays like this:

[1, 2, 3, 4, 5, 6]

Using Enumerable.Concat() method

To concatenate the two arrays into a single array, we can use the Enumerable.Concat() method in C#.

Note: The Enumberable.Concat() is available in System.Linq namespace.

Here is an example:

using System;using System.Linq;class ConcatenateArrays {  static void Main() {   int[] array1 = { 1, 2, 3 };   int[] array2 = { 4, 5, 6 };   int[] result = array1.Concat(array2).ToArray();   Console.WriteLine(String.Join(",", result));  }}

Output:

[1, 2, 3, 4, 5, 6]

Using AddRange() method

Similarly, we can use the AddRange() method in C# to join two arrays into a single array.

Example:

using System;using System.Collections.Generic;class ConcatenateArrays {  static void Main() {      int[] arr1 = {1, 2, 3};      int[] arr2 = {4, 5, 6};      var myList = new List<int>();      myList.AddRange(arr1);      myList.AddRange(arr2);      int[] result = myList.ToArray();   Console.WriteLine(String.Join(",", result));  }}

In the above code, we have first initialized an empty integer List and then added arr1 and arr2 to the List using the AddRange() method, at the end we have converted a list to an array using ToArray() method.