Struct from C to C#

[ulmus]

I receive data from usb in specific record structure (cant change it). I have method to read buffer to Byte[]. Simple struct union would do the job but c# is broken in that case.
My struct in C is:

typedef union
{
    struct
    {
        int Value;
        int ValueFromADC;
        int Zero;
        int Temperature;
        int RefTemperature;
 
        unsigned char Metal;
        unsigned char Range;
        unsigned char Year;
        unsigned char Month;
 
        unsigned char Day;
        unsigned char Hour;
        unsigned char Minute;
        unsigned char Second;
 
        unsigned char MemoryStatus;
        unsigned char Bank;
        unsigned char Cell;
        unsigned char NC;//not used structure element
    };
    unsigned int Data[8];
    unsigned char Bytes[32];
}Value_t;
 

I am trying write received data from usb into Byte[] struct field, and read from structure using proper fields. Union like above would do tha thing but c#....
I tried almost everything, amongs the others, something like:

    [StructLayout(LayoutKind.Explicit, Size = 32)]
    public struct Value_t
    {
        //////////////////////////////
        [FieldOffset(0)][MarshalAs(UnmanagedType.LPArray, SizeConst=32)]
        public Byte[] Bytes;
        //////////////////////////////
        [FieldOffset(0)]public Int32 Value;
        [FieldOffset(4)]public Int32 ValueFromADC;
        [FieldOffset(8)]public Int32 Zero;
        [FieldOffset(12)]public Int32 Temperature;
        [FieldOffset(16)]public Int32 RefTemperature;
        [FieldOffset(20)]public Byte Metal;
        [FieldOffset(21)]public Byte Range;
        [FieldOffset(22)]public Byte Year;
        [FieldOffset(23)]public Byte Month;
        [FieldOffset(24)]public Byte Day;
        [FieldOffset(25)]public Byte Hour;
        [FieldOffset(26)]public Byte Minute;
        [FieldOffset(27)]public Byte Second;
        [FieldOffset(28)]public Byte MemoryStatus;
        [FieldOffset(29)]public Byte Bank;
        [FieldOffset(30)]public Byte Cell;
        [FieldOffset(31)]public Byte NC;
    };
 

It compiles but after running it complains:
".... because it contains an object field at offset 0 that is incorrectly aligned or overlapped by a non-object field." sic!!! WTF?!

Anybody has any piece of advice or solution for that thing?

[ulmus]

Finally i did this, it is not as fast as union but does what it should do :

    public struct Wynik
    {
        public Byte[] Bytes;
        //////////////////////////////////////
        public Int32 Value          { get { return BitConverter.ToInt32(Bytes, 0); } set { BitConverter.GetBytes(value).CopyTo(Bytes, 0); } }
        public Int32 ValueFromADC   { get { return BitConverter.ToInt32(Bytes, 4); } set { BitConverter.GetBytes(value).CopyTo(Bytes, 4); } }
        public Int32 Zero           { get { return BitConverter.ToInt32(Bytes, 8); } set { BitConverter.GetBytes(value).CopyTo(Bytes, 8); } }
        public Int32 Temperature    { get { return BitConverter.ToInt32(Bytes, 12); } set { BitConverter.GetBytes(value).CopyTo(Bytes, 12); } }
        public Int32 RefTemperature { get { return BitConverter.ToInt32(Bytes, 16); } set { BitConverter.GetBytes(value).CopyTo(Bytes, 16); } }
 
        public Byte Metal           { get { return Bytes[20]; } set { Bytes[20] = value; } }
        public Byte Range           { get { return Bytes[21]; } set { Bytes[21] = value; } }
        public Byte Year            { get { return Bytes[22]; } set { Bytes[22] = value; } }//BCD
        public Byte Month           { get { return Bytes[23]; } set { Bytes[23] = value; } }//BCD
        public Byte Day             { get { return Bytes[24]; } set { Bytes[24] = value; } }//BCD
        public Byte Hour            { get { return Bytes[25]; } set { Bytes[25] = value; } }//BCD
        public Byte Minute          { get { return Bytes[26]; } set { Bytes[26] = value; } }//BCD
        public Byte Second          { get { return Bytes[27]; } set { Bytes[27] = value; } }//BCD
        public Byte MemoryStatus    { get { return Bytes[28]; } set { Bytes[28] = value; } }
        public Byte Bank            { get { return Bytes[29]; } set { Bytes[29] = value; } }
        public Byte Cell            { get { return Bytes[30]; } set { Bytes[30] = value; } }
        public Byte NC              { get { return Bytes[31]; } set { Bytes[31] = value; } }//not used structure element
    };
 
 

One thing more:
how can i exchange

BitConverter.GetBytes(value).CopyTo(Bytes, 12);

into something copying direct to proper offset of byte array?
just opposite to:

BitConverter.ToInt32(Bytes, 12);

instead of copying array into array, like i did.