Arrays

An array is a data structure used in C# to store a sequential collection of elements. Its size is immutable (cannot be changed after creation). The elements of an array are all of the same type, but it is possible to define a C# array that can hold elements of any type by specifying the type of the array as an object. In C#, all types directly or indirectly inherit from Object.

Syntax

There are several ways to create an array in C#:

// Create a variable of type "type[]" without initializing it:
type[] arrayName;

// Create the array variable and initialize it with an array of N items:
type[] arrayName = new type[N];

// Create the array variable and initialize it by specifying the contents:
type[] arrayName = new type[] { value1, value2, value3, ... valueN };

// Alternative way of creating the array and specifying the contents:
type[] arrayName = { value1, value2, value3, ... valueN };

Note: Arrays in C# have a set size, meaning the number of elements they hold cannot be changed once the array has been created.

Example

Each element in an array is assigned a specific index starting at zero. To access or modify an element in the array, you refer to it by its index and operate on it accordingly.

using System;

public class Example
{
  public static void Main(string[] args)
  {
    char[] vowels = {'a', 'e', 'i', 'o', 'u'};
    //      indexes:  0    1    2    3    4

    Console.WriteLine(vowels[0]); // Output: a

    vowels[0] = 'r';

    Console.WriteLine(vowels[0]); // Output: r
  }
}

In the example above, an array of chars was initialized with all the vowels. The first element in the array at index 0 was printed. Then, the element at index 0 was modified by assigning it a new value of 'r'. Then, the value at index 0 was printed again.

Array Methods

Arrays in C# are objects, not just contiguous blocks of memory as in C and C++. Array is the base type of all arrays, and any array can use the properties and methods of the Array object, a few of which are listed below: