Using Arrays in C#

Arrays :

Arrays can be defined as a data structure for storing group of elements.
It can contain element of any data type. Following are examples of various
data types :

string[] strArray = new string[5];
int[] intArray = new int[3];

double[] dblArray = new double[4];

char[] charArray = new char[10];

bool[] boolArray = new bool[2];

Arrays can be of two types, fixed length (static) array and dynamic array.

Fixed arrays has predefined size. An example is :

int[] staticArray = new int[6];

Dynamic Arrays can store any number of items as it doesn't have a predefined
size. An example is :

int[] intArr;

Initialization and Accessing:

Arrays can be initialized in two ways :

int[] intArray= new int[3] {1, 2, 3};

or as follows :

int[] intArr= new int[3];

intArr[0] = 1;

intArr[1] = 2;

intArr[2] = 3;

Dynamic Array can be initialized as :

string[] strArr = new string[] { "Apple", "Orange", "Pears", "Kiwi","Pomegranate" };

Values of array can be accessed as follows in ASP.NET :

Response.Write(strArr[1]) 

which will display the result as "Orange".

Using foreach Loop to access array elements :

Following is an example :

foreach (string str in strArray)

{

    Response.Write(str);

}

Array Types :

Arrays are of 4 different types :

(1) Single Dimensional :

These are arrays with one dimension as following examples :

int[] intArr = new int[4] {1, 2, 3, 4};
string[] names = new string[3] {"John", "Jerry", "Mary"};

(2) Multi Dimensional :

These are arrays with multiple dimensions as following examples :



int[,] intArr = new int[2, 3] { {1, 2, 3}, {3, 4, 5} };
string[,] strArr = new string[2, 2] { {"abc","def"}, {"ghi","jkl"} };
It can be used as a dynamic as follows :
int[,] intArr = new int[,] { {1, 2, 3}, {3, 4, 5} };
string[,] strArr = new string[,] { {"abc","def"}, {"ghi","jkl"} };

(3) Jagged Array :

These are array of arrays. Following is an example :

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

(4) Mixed Array :

It is a combination of multi dimension array and jagged array


Properties of Arrays :

It has many properties and commonly used one is Length and Rank.

Length contains total number of elements in all the dimensions of the array.

In this example :

string[] strArr = new string[] { "Apple", "Orange", "Pears", "Kiwi","Pomegranate" };




Response.Write(strArr.Length);




will display the output as 5




Rank contains number of  dimensions of the array




Response.Write(strArr.Rank);




will display the output as 1