Multidimensional array in C#

INDEX

• What is an array?
• What is a multidimensional array?
• 2d and 3d arrays
• Examples

1. What is an Array?

Arrays are used to store multiple values in a single variable instead of in  separate variables. It can be single dimensional, multidimensional, or jagged.

2. What is a multidimensional array?

It is an array of arrays and has more than one dimension. The most common is a two-dimensional array, i.e., 2D.

3. What is 2D?

A 2D array is a matrix that consists of rows and columns.

3.1 2D array with an int data type without specifying the index

int[,] arrayNumbers = new int[,] { {1, 2}, {3, 4} };

	Col 0	Col 1
Row 0	1	2
Row 1	3	4

3.1.1 Output:

Console.WriteLine(arrayNumbers[0][1]);
Console.WriteLine(arrayNumbers[1][0]);
2
3

3.2 2D array with int data type and specified index

int[,] arrayNumbers = new int[3,2] { {1, 2}, {3, 4}, {5,6} };

	Col 0	Col 1
Row 0	1	2
Row 1	3	4
Row 2	5	6

3.2.1 Output:

Console.WriteLine(arrayNumbers[0][1]);
Console.WriteLine(arrayNumbers[1][0]);
2
3

3.3 2D array with string data type

string[,] arrayCities = new string[2,2] { {”Chennai”, “Bangalore”}, {”Delhi”, “Pune”} };

	Col 0	Col 1
Row 0	Chennai	Bangalore
Row 1	Delhi	Pune

3.3.1 Output:

Console.WriteLine(arrayNumbers[0][1]);
Console.WriteLine(arrayNumbers[1][0]);
Bangalore
Delhi

4. What is 3D?

3D arrays are used to hold multiple 2D arrays, and they supports up to 32 dimensions. It can be declared by adding commas in the square brackets. For example, [,] - two-dimensional array
[, ,] - three-dimensional array
[, , ,] - four-dimensional array, and so on.

1st index: indicates the number of layers
2nd index: number of rows
3rd index: number of cols

4.1 Examples

4.1.1 Single-layer

int[, ,] array3d1 = new int[1, 2, 2]{
                { { 1, 2}, { 3, 4} }
            };

4.1.2 Two layers with 2 rows and 2 columns

int[, ,] array3d2 = new int[2, 2, 2]{
                { {1, 2}, {3, 4} },
                { {5, 6}, {7, 8} }
            };

4.1.3 Two layers with 2 rows and 3 columns

int[, ,] array3d3 = new int[2, 2, 3]{
                { { 1, 2, 3}, {4, 5, 6} },
                { { 7, 8, 9}, {10, 11, 12} }
            };

4.1.4 Output:

Console.WriteLine(array3d1[0, 0, 0]); // Output = 1
Console.WriteLine(array3d1[0, 0, 1]); // Output = 2
Console.WriteLine(array3d2[0, 1, 0]); // Output = 3
Console.WriteLine(array3d2[1, 1, 1]); // Output = 7
Console.WriteLine(array3d3[0, 1, 2]); // Output = 6
Console.WriteLine(array3d4[1, 0, 2]); // Output = 9