Question

What is the best way to get a byte array from a struct to send over TCP sockets? I’m using .Net (VB or C#).

Answer 1

One option is to marshal the native representation of the struct into a buffer directly, similar to how memcpy works in C.

You would need to add the appropriate attribute to your struct,

  [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi, Pack=1)] 

Then you can serialize it using:

    /// <summary>     /// Serializes the specified object into a byte array.     /// </summary>     /// <param name='nativeObject'>The object to serialize.</param>     /// <returns></returns>     public static byte[] Serialize(object obj)     {         Type objectType = obj.GetType();         int objectSize = Marshal.SizeOf(obj);         IntPtr buffer = Marshal.AllocHGlobal(objectSize);         Marshal.StructureToPtr(obj, buffer, false);         byte[] array = new byte[objectSize];         Marshal.Copy(buffer, array , 0, objectSize);         Marshal.FreeHGlobal(buffer);         return array;     } 

Still, this is by far the least portable solution. Both sides will need to use the same alignment and endianness, and you will need to implement versioning yourself if you will ever need to change the struct itself.

In most cases, your serialization format shouldn’t be a direct copy of your internal data structures.