How to marshall fixed byte array for C function

Question

Hi I have been working to create a wrapper for dll of a third party C library to be used in C#.

Suppose I have C function from the library:

void functionA(byte data[16], byte buffer[8]);

Is it correct for the following code to be used to wrap the code above ?:

[DllImport("C.dll",CallingConvention=CallingConvention.Cdecl)]
static extern void functionA(byte[] data, byte[] buffer)

See here: stackoverflow.com/questions/9892734/….

wohlstad
– wohlstad

2022-06-11 05:17:19 +00:00
Commented Jun 11, 2022 at 5:17 — wohlstad
– wohlstad, Commented Jun 11, 2022 at 5:17

Charlieface · Accepted Answer · 2022-06-12 02:07:06Z

-1

No, that declaration would only be valid for byte *data, which is a pointer to an array.

What you have is a fixed size array, for which you need the following

[DllImport("C.dll", CallingConvention = CallingConvention.Cdecl)]
static extern void functionA(
  [MarshalAs(UnmanagedType.ByValArray, SizeConst = 16]
  byte[] data,
  [MarshalAs(UnmanagedType.ByValArray, SizeConst = 8]
  byte[] buffer)

answered Jun 12, 2022 at 2:07

Charlieface

78.6k8 gold badges35 silver badges77 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

How to marshall fixed byte array for C function

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related