using System;

public class Program

{

    public static void Main()

    {

        Object objectNull = null;

        String stringNull = null;

        Object objectEmpty = String.Empty;

        String stringEmpty = String.Empty;

        var objectNullConvertToString = Convert.ToString(objectNull);

        var stringNullConvertToString = Convert.ToString(stringNull);

        var objectEmptyConvertToString = Convert.ToString(objectEmpty);

        var stringEmptyConvertToString = Convert.ToString(stringEmpty);

        if (objectNullConvertToString == null)

            Console.WriteLine("objectNullConvertToString == null");

        if (objectNullConvertToString == String.Empty)

            Console.WriteLine("objectNullConvertToString == String.Empty");

        if (stringNullConvertToString == null)

            Console.WriteLine("stringNullConvertToString == null");

        if (stringNullConvertToString == String.Empty)

            Console.WriteLine("stringNullConvertToString == String.Empty");

        if (objectEmptyConvertToString == null)

            Console.WriteLine("objectEmptyConvertToString == null");

        if (objectEmptyConvertToString == String.Empty)

            Console.WriteLine("objectEmptyConvertToString == String.Empty");

        if (stringEmptyConvertToString == null)

            Console.WriteLine("stringEmptyConvertToString == null");

        if (stringEmptyConvertToString == String.Empty)

            Console.WriteLine("stringEmptyConvertToString == String.Empty");

    }

}