Methods in C Sharp

Question

Sir,

 

I am starting methods in c sharp and i have confustion with pass by value and reference.

also i get confused what passes incase of arrays.

 

example in the below code of Write a method that checks whether an element, from a certain position in an array is greater than its two neighbours.

static void Main()
{
int[] array=new[] {1,2,3,2,5,8,7,9};
int position = int.Parse(Console.ReadLine());
ElementCheck(position, array);
}
static void ElementCheck(int newposition, int[] array)
{
if ((array[newposition]> array[newposition-1]) && (array[newposition]> array[newposition+1]))
{
Console.WriteLine("Greater");
}
else
{
Console.WriteLine("Not greater");
}
}

Questions are :

 

1. I am calling ElementCheck(position, array); but how will all the elements of array pass to the elementcheck?

 

Also, can we return string ...for exampe like this below:

static void Main()
{
int[] array=new[] {1,2,3,2,5,8,7,9};
int position = int.Parse(Console.ReadLine());
ElementCheck(position, array);
}
static string ElementCheck(int newposition, int[] array)
{
if ((array[newposition]> array[newposition-1]) && (array[newposition]> array[newposition+1]))
{
return greater?;
}
else
{
return notgreater?;
}
}

This code gives me error. Why?