Accessing fields in a C structure via C#

[Ted Sung]

Hi,

I'm using P/Invoke to call some C functions from a DLL.
My C function returns a pointer to a large C structure. I store this
returned pointer in an IntPtr C# variable. I would now like
to access the data in this structure.

What is the best way to do this? The structure is so large that I can't
lay it out as a C# struct. What else could I do?

Thanks,

Ted

[Mattias Sjögren]

What is the best way to do this? The structure is so large that I can't
lay it out as a C# struct. What else could I do?

Really? I didn't know there was any size limitation on structs? So
exactly how large is it?

I guess you could use unsafe code, cast to a pointer of the
appropriate type and then use that to read/write members in the
struct.

Mattias

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Mattias Sjögren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.

[Eric Gunnerson [MS]]

There is no limit on the struct size.

Your best bet is to post with the C++ function header. the framework.interop
newgroup is a good one to ask this sort of question on.

--
Eric Gunnerson

Visit the C# product team at http://www.csharp.net
Eric's blog is at http://weblogs.asp.net/ericgu/

This posting is provided "AS IS" with no warranties, and confers no rights.
"Ted Sung" <te**@intex.com> wrote in message
news:86**************************@posting.google.c om...

Hi,

I'm using P/Invoke to call some C functions from a DLL.
My C function returns a pointer to a large C structure. I store this
returned pointer in an IntPtr C# variable. I would now like
to access the data in this structure.

What is the best way to do this? The structure is so large that I can't
lay it out as a C# struct. What else could I do?

Thanks,

Ted