How to Get the Size of an Array in C#

1. Get the Size of Array With the Array.Length Property in C#
2. Get Size of Each Dimension of a Multi-Dimensional Array With the Array.Rank Property and the Array.GetLength() Function in C#

This tutorial will discuss methods to get the size of an array in C#.

Get the Size of Array With the Array.Length Property in C#

The size of an array means the total number of elements an array can store in it. The Array.Length property gives us the total size of an array in C#. The following code example shows us how to get the length of an array with the Array.Length property in C#.

using System;

namespace size_of_array {
  class Program {
    static void method1() {
      int[] a = new int[17];
      Console.WriteLine(a.Length);
    }
    static void Main(string[] args) {
      method1();
    }
  }
}

Output:

17

In the above code, we get the length of the a array with the a.Length property in C#. This method can also be used to get the total size of a multi-dimensional array. The code to determine the total size of a 2-D array is given below.

using System;

namespace size_of_array {
  class Program {
    static void method1() {
      int[,] a = new int[17, 2];
      Console.WriteLine(a.Length);
    }
    static void Main(string[] args) {
      method1();
    }
  }
}

Output:

34

Get Size of Each Dimension of a Multi-Dimensional Array With the Array.Rank Property and the Array.GetLength() Function in C#

Suppose we have a multi-dimensional array, and we want to get each dimension’s size inside the multi-dimensional array. In that case, we have to use the Array.Rank property and the [Array.GetLength() function](https://learn.microsoft.com/en-us/dotnet/api/system.array.getlength?view=net-8.0&viewFallbackFrom=net-5.0%2F) in C#. The Array.Rank property gives us the number of dimensions inside the array. The Array.GetLength(i) function gives us the size of the i dimension of the array. The following code example shows us how we can get the total size of each dimension of a multi-dimensional array with the Array.Rank property and the Array.GetLength() function in C#.

using System;

namespace size_of_array {
  class Program {
    static void method2() {
      int[,] a = new int[17, 2];
      int i = a.Rank;
      for (int x = 0; x < i; x++) {
        Console.WriteLine(a.GetLength(x));
      }
    }
    static void Main(string[] args) {
      method2();
    }
  }
}

Output:

17
2

In the above code, we print the size of each dimension of the multi-dimensional array a with the a.Rank property and the a.GetLength(x) function. We get the number of dimensions inside the a array with the a.Rank property and iterate through each dimension using a for loop. Then we print each dimension’s size with the a.GetLength(x) function, where x is the index of the dimension.