Question

I am trying a simple Extension Method example and am unable to increment or decrement an int.
Here is the code

static class ExtensionMethodsExp
{
    public static void Print(this object o)
    {
        Console.WriteLine("This is print: {0}", o.ToString());
    }

    public static int Double(this int i)
    {
        return i * 2;
    }
    public static int Decrement(this int i)
    {
         return i--;
    }

    public static int Increment(this int i)
    {
        return i++;

    }
}

}

Program Code is

class Program
{
    static void Main(string[] args)
    {

       int myNumber = 10;
       myNumber.Print();

       myNumber = myNumber.Double();
       myNumber.Print();

       myNumber = myNumber.Decrement(); 
       myNumber.Print();

       myNumber = myNumber.Increment();
       myNumber.Print();

       myNumber.Increment().Double().Print();
       Console.ReadKey();
    }
}

I am getting following as output

This is print: 10

This is print: 20

This is print: 20

This is print: 20

This is print: 40

Any idea why Decrement or Increment should not work here. Is there something I am missing?
thanks

Answer 1

Try this:

public static int Decrement(this int i)
{
     return --i;
}

public static int Increment(this int i)
{
    return ++i;
}