What a Jagged Array Is

In this article we learn what a jagged array is and how we use jagged arrays in our applications.

A jagged array is an array of arrays.

Problem

Suppose I run an institute and I have 4 students and all 4 students have enrolled in 2 courses.
Let's make a table for better visualization.

Student Name Subject Name.

Student Name	Subject Name
Pramod	C# SQL Server Java jQuery
Ravi	C#
Rahul	Android Window Phone Development iOS development
Deepak	Html5 CSS3

Solution

We can do this to use a jagged array.

First create a string array to store student names.

string[] studentArray = new string[4];
studentArray[0] = "Pramod";
studentArray[1] = "Ravi";
studentArray[2] = "Rahul";
studentArray[3] = "Deepak";

We want 4 string arrays so we specified the size of our jagged array as 4.

string[][] jaggedArray = new string[4][];

Let's specify the size of the first string array within jagged array as 4.

jaggedArray[0] = new string[4];

For the second, third and fourth string array length in jagged array is 1,3,2 respectively.

jaggedArray[1] = new string[1];
jaggedArray[2] = new string[3];
jaggedArray[3] = new string[2];

Let's store some data in the jagged array.

jaggedArray[0][0] = "C#";
jaggedArray[0][1] = "SQL Server";
jaggedArray[0][2] = "Java";
jaggedArray[0][3] = "jQuery";

jaggedArray[1][0] = "C#";

jaggedArray[2][0] = "Android";
jaggedArray[2][1] = "Window Phone Development";
jaggedArray[2][2] = "iOS development";

jaggedArray[3][0] = "Html5";
jaggedArray[3][1] = "CSS3";

Let's print this using the following code.

for (int i = 0; i < jaggedArray.Length; i++)
{
      string[] anotherArray =jaggedArray[i];
      Console.WriteLine(studentArray[i]);
      Console.WriteLine();
      for (int j = 0; j < anotherArray.Length; j++)
      {
            Console.WriteLine(anotherArray[j]);
      }
      Console.WriteLine("=========================");
}
Console.ReadLine();

Output