Hi Group,

I am trying to define a class that has a fixed size array of a
structure containing a fixed size array of a structure.

I am using System.Runtime.InteropServices and trying to define the
fixed size using [MarshalAs(UnmanagedType.ByValArray, SizeConst = 10)]

In the attached console application example when I try to address the
fields in the class I get an execption.
Also when I try to examine the sub structures in the debugger I get
NULL.

So I assume I need to use new to create the fields - I have tried
several combinations without any success.

Does anyone konw what I am doing wrong in this example?

Thanks

Mark

using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;

namespace ArrayofStruct
{
   class Program
   {
       static void Main(string[] args)
       {
           toplevel firstlevel = new toplevel();

           // firstlevel.

firstlevel.level1[1].subelevel1_array[1].sublevel2_array[1] = 0;
       }
   }

   public struct sublevel2 //Sublevel 2 struct containing array 10 of
UInt16
   {
       public UInt16 sublevel2_field1;
       [MarshalAs(UnmanagedType.ByValArray, SizeConst = 10)]
       public UInt16[] sublevel2_array;
   }

   public struct sublevel1  //Sublevel 1 struct containing array of
10 of level2 struct
   {
       public UInt16 sublevel1_field1;
       [MarshalAs(UnmanagedType.ByValArray, SizeConst = 10)]
       public sublevel2[] subelevel1_array;
   }

   public class toplevel  //Toplevel Class containing array 10 of
level1 struct
   {
       public UInt32 field1;
       [MarshalAs(UnmanagedType.ByValArray, SizeConst = 10)]
       public sublevel1 [] level1;
   }
}