In C #, struct and byte streams are converted to each other.

Because the program must communicate with the program developed by C ++, the communication data is the converted byte stream of the struct, therefore, C # Must be able to smoothly convert bytes into C # struct.

 

1. Define the C # struct corresponding to C ++
   

    

   Code

      // C ++ struct
   Struct tagCheakUser
   {
   Char userName [12];
   Char pwd [32];
   }
   
   
   
   // Corresponding C # struct
   [StructLayout (LayoutKind. Sequential, Pack = 1)]
   Public struct CheckUser
   {
   [Financialas (UnmanagedType. ByValTStr, SizeConst = 12)]
   Public string userName;
   [Financialas (UnmanagedType. ByValTStr, SizeConst = 32)]
   Public string pwd;
   }
   

    

   
   In the header file definition of C ++, # pragma pack 1 bytes are aligned by 1, so the structure of C # must also be added with the corresponding features, LayoutKind. the Sequential attribute layout the struct in sequence when exported to the unmanaged memory. For the char array type of C ++, string can be directly used in C #. Of course, you must also add the characteristics and length constraints of the mail.
2. Mutual conversion between struct and byte []
   

    

   Code

      //convert structure T to byte[] 
   public static byte[] ConvertStructToBytes(object objStruct)
   {
       //get the size of structure
       int size = Marshal.SizeOf(objStruct);
       //define buffer arrays
       byte[] buffer = new byte[size];
       //Alloc unmanaged memory and Copy structure to unmanaged memory
       IntPtr ipStruct = Marshal.AllocHGlobal(size);
       Marshal.StructureToPtr(objStruct, ipStruct, false);
       //Copy to the byte array
       Marshal.Copy(ipStruct, buffer, 0, size);
       //Free unmanaged  memory
       Marshal.FreeHGlobal(ipStruct);
       return buffer;
   }
   
   //convert byte array to sturcture
   public static TR ConvertBytesToSturct<TR>(byte[] datas)
   {
       //get size of sturcture
       int size = Marshal.SizeOf(typeof(TR));
       //can not be convert
       if (datas.Length < size)
       {
           return