public static class Program
    {

        [StructLayout(LayoutKind.Explicit)]
        public struct SafePtr
        {
            // (1)
            public class ReferenceType
            {
                public object Reference;
            }

            // (2)
            public class IntPtrWrapper
            {
                public IntPtr IntPtr;
            }

            // (3)
            [FieldOffset(0)]
            private ReferenceType Obj;

            // (4)
            [FieldOffset(0)]
            private IntPtrWrapper Pointer;

            public static SafePtr Create(object obj)
            {
                return new SafePtr { Obj = new ReferenceType { Reference = obj } };
            }

            public static SafePtr Create(IntPtr rIntPtr)
            {
                return new SafePtr { Pointer = new IntPtrWrapper { IntPtr = rIntPtr } };
            }

            // (5)
            public IntPtr IntPtr
            {
                get { return Pointer.IntPtr; }
                set { Pointer.IntPtr = value; }
            }

            // (6)
            public Object Object
            {
                get { return Obj.Reference; }
                set { Obj.Reference = value; }
            }

            public void SetPointer(SafePtr another)
            {
                Pointer.IntPtr = another.Pointer.IntPtr;
            }
        }

        static void Main(string[] args)
        {

            var str1 = "Roman ";
            var safeptr1 = SafePtr.Create(str1);
            Console.WriteLine("{0} = {1}", str1, safeptr1.IntPtr.ToInt32());
            var str2 = "Mejtes";
            str1 += str2;
            var safeptr2 = SafePtr.Create(str1);
            Console.WriteLine("{0} = {1}", str1, safeptr2.IntPtr.ToInt32());
            Console.ReadKey();
        }

    }