Let us understand the difference between initialization and assignment of values.
Declaring an array.
int [] n // declaring
Declaring an array does not initialize the array in the memory. When the array variable is initialized, you can assign values to the array. Array is a reference type, so you need to use the new keyword to create an instance of the array.
int n= new int[10]; // initialization
Let’s assign value. You can assign values to individual array elements, by using the index number −
n[0] = 100; n[1] = 200
With C#, you can declare, initialize and assign values to an array in a single line −
int n= new int[10] {100, 200, 300, 400, 500};
When you create an array, C# compiler implicitly initializes each array element to a default value depending on the array type. For example, for an int array all elements are initialized to 0.