This artical will help you to understand the power or the recurssion in the .NET

Recursion :
Recursion means defining a function in terms of itself; in other words, the function calls itself.

The following example shows recursion in action.
This example will returns the sqaure of even numbers upto the upperLimit starting from the startNumber ascending order, and from there it returns the numbers in decending order.

let us see the example:

publicstatic int methodCall(int startNumber,int upperLimit)
        {
          if (startNumber < upperLimit)

            {

               Console.Write("  " + startNumber);

 methodCall(startNumber * 2,upperLimit);
    }

    Console.Write("  " + startNumber);


            return startNumber;


        }

Call this Method in the main method as

methodCall(2,32);

OUTPUT:
2 4 8 16 32 16 8 4 2

Conclusion:

With out using any loops we can achieve the desired result with recursion, but here the problem is function calling.