using System;

public class Program

{

    public static void Main()

    {

        TestCastingFromObjectToDouble();

    }

    public static void TestCastingFromObjectToDouble()

    {

        Log("The purpose of this test is to show how an object holding an int value can be cast to a double.");

        Log();

        int int_a = 5;

        Log("The original int we're working with is int_a = " + int_a);

        double dbl_intCastedToDouble = (double)int_a;

        Log("We can easily cast this int to a double: " + dbl_intCastedToDouble);

        Log();

        object obj_intCastedToObject = (object)int_a;

        Log("We can easily also cast an int to an object: " + obj_intCastedToObject);

        Log();

        Log("If we can cast an int to a double, can we cast the object to a double?");

        Log("No. We can't just do double d = (double)obj. If you try you get an System.InvalidCastException.");

        Log("Why? Because the object is not a double. It's actually an int.");

        //double dbl_objectCastedToDouble = (double)obj_intCastedToObject; // 'System.InvalidCastException'

        Log();

        double dbl_objectCastedFirstToIntThenDouble = (double)(int)obj_intCastedToObject;

        Log("What we can do though is first cast it to an int, then cast it to a double!");

        Log("Like this: double dbl_objectCastedFirstToIntThenDouble = (double)(int)obj_intCastedToObject;");

        Log("double dbl_objectCastedFirstToIntThenDouble is now " + dbl_objectCastedFirstToIntThenDouble);

        Log();

        Log("Alternatively instead of casting we could use: Convert.ToDouble(obj_intCastedToObject);");

    }

    public static void Log(string msg)

    {

        Console.WriteLine(msg);

    }

    public static void Log()

    {

        Console.WriteLine();

    }

}