how can i define a struct with a dynamic sized array?
is it right?
struct MyStruc {
public int len;
[MarshalAs(UnmanagedType.LPArray, SizeParamIndex=0)]
public int buf[];
}
1 Answer
Assuming that you want a struct containing a pointer to the array.
Declare the pointer to the array as IntPtr and marshal the array contents manually with Marshal.AllocHGlobal, Marshal.Copy etc.
Assuming that you want a variable sized struct rather than a struct containing a pointer to the array.
You cannot marshal a variable sized struct using p/invoke. You have at least these two options:
- Break the struct into two parameters.
- Marshal the struct manually with
Marshal.AllocHGlobal,Marshal.Copyetc.
answered Apr 2, 2014 at 12:41
David Heffernan
616k46 gold badges1.1k silver badges1.5k bronze badges
11 Comments
golazo
Ok i understand but i don't want to work with IntPtr in c# :( but i guess, i haven't got an other way.
David Heffernan
Which of my two assumptions is correct. Showing the C++ declaration of the type would have helped.
golazo
Actually, i'm using a dll and i haven't got dll codes. But i have got dlls' definition of struct. the definition like this: struct MyStruc { int len; int buf[1]; }
golazo
But when i talked with developer who is developed this dll, he said to me this buf hasn't got fixed size, it can be dynamicaly.
golazo
I guess, dll side is using pointer to buff and return an array.
|
List<int>?IntPtror gounsafe(the latter might be easier to get things working correctly).ByValArrayis for inline arrays whose size is known at compile time.