convert struct handle from managed into unmanaged C++/CLI

Question

In C#, I defined a struct:

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct MyObject
{
   [MarshalAs(UnmanagedType.LPWStr)]
   publ         


        

Answer 1

You probably mean:

struct MyUnmanagedStruct {
    LPWSTR var1, var2;
};

Then you can use Marshal.StructureToPtras suggested by Botz3000. Otherwise C#'s

public struct MyObject {
   public String var1;
   public String var2;
}

and C++/CLI's

public struct value MyObject {
   public String^ var1;
   public String^ var2;
}

are completely equivalent, assuming your're you're using the same System.String on both sides.

Answer 2

Marshal::PtrToStructure does the opposite of what you want, it converts an unmanaged pointer to a managed object. You want Marshal::StructureToPtr.

Also, you would need to define an unmanaged class, because MyObject is a Managed Type. Assuming you have done that, you could do it like this (just converted this from the C# sample):

IntPtr pnt = Marshal::AllocHGlobal(Marshal::SizeOf(configObject)); 
Marshal.StructureToPtr(configObject, pnt, false);

You then have a pointer to the data, which you can memcpy or whatever into your native struct.

But MyObject is and will stay a managed type. If you want a truly unmanaged type, you have to define one that matches the managed struct.

Just wondering, why are you using unmanaged LPWSTR in a managed struct?