All possible array initialization syntaxes

Question

What are all the array initialization syntaxes that are possible with C#?

Answer 1

In case you want to initialize a fixed array of pre-initialized equal (non-null or other than default) elements, use this:

var array = Enumerable.Repeat(string.Empty, 37).ToArray();

Also please take part in this discussion.

Answer 2

Example to create an array of a custom class

Below is the class definition.

public class DummyUser
{
    public string email { get; set; }
    public string language { get; set; }
}

This is how you can initialize the array:

private DummyUser[] arrDummyUser = new DummyUser[]
{
    new DummyUser{
       email = "[e-mail]",
       language = "English"
    },
    new DummyUser{
       email = "[e-mail]",
       language = "Spanish"
    }
};

Answer 3

int[] array = new int[4]; 
array[0] = 10;
array[1] = 20;
array[2] = 30;

or

string[] week = new string[] {"Sunday","Monday","Tuesday"};

or

string[] array = { "Sunday" , "Monday" };

and in multi dimensional array

    Dim i, j As Integer
    Dim strArr(1, 2) As String

    strArr(0, 0) = "First (0,0)"
    strArr(0, 1) = "Second (0,1)"

    strArr(1, 0) = "Third (1,0)"
    strArr(1, 1) = "Fourth (1,1)"

Answer 4

For Class initialization:
var page1 = new Class1();
var page2 = new Class2();
var pages = new UIViewController[] { page1, page2 };

Answer 5

Enumerable.Repeat(String.Empty, count).ToArray()

Will create array of empty strings repeated 'count' times. In case you want to initialize array with same yet special default element value. Careful with reference types, all elements will refer same object.

Answer 6

Repeat without LINQ:

float[] floats = System.Array.ConvertAll(new float[16], v => 1.0f);