how to properly initialize an array?

Question

I am trying to understand how arrays work and ran into a problem. I have understood that arrays are a fixed data type and once defined cannot go out of it's bounds. However, the below method seems to be working fine and I don't understand why. Do I have an incomplete understanding of arrays

    private static int[] return_Array()
    {
       int[] arr = new int[5];

       arr = [1,2,3,4,5,6];

       return arr;
    } 

Even if I did arr = new int[] {1,2,3,4,5,6,7}; it's working without any error

Shouldn't I get an Index was outside the bounds of the array error in both scenarios?

Answer 1

You are not adding values to the array, you are replacing it.

int[] arr = new int[5]; --> int[] arr = [0,0,0,0,0]
arr = [1,2,3,4,5,6];    --> int[] arr = new int[] {1,2,3,4,5,6}