Csharp calling C++ Managed code using Byte array reference

[Trev]

I can call C++ methods using byte arrays as values but I wish to call a C++
method using a reference to an empty byte array that is then initiaised to a
set size by the c++ method and populated within the c++ mthod before
returning back to the c# code.

E.g.

c# call

byte[] data;
cpp_method.getD ata(ref data);

c++ method signature

int getData (System::Byte __gc * __gc * byteArray __gc[])

However this is not allowed.

Can anybody help me in how I need to call a C++ managed method passing a
reference to a byte array that is going to be initialised in the c++ layer.

Thanks

[Willy Denoyette [MVP]]

Re: Csharp calling C++ Managed code using Byte array reference

Try this:

// CLS compliant function taking a REF array
void GetArray( System::Byte (*bArray) __gc[])
{
*bArray = new System::Byte[123];
}

Willy.

"Trev" <Trev@discussio ns.microsoft.co m> wrote in message
news:FFB03AC3-3535-46F6-816F-9EFF77ADD15E@mi crosoft.com...[color=blue]
>I can call C++ methods using byte arrays as values but I wish to call a C++
> method using a reference to an empty byte array that is then initiaised to
> a
> set size by the c++ method and populated within the c++ mthod before
> returning back to the c# code.
>
> E.g.
>
> c# call
>
> byte[] data;
> cpp_method.getD ata(ref data);
>
> c++ method signature
>
> int getData (System::Byte __gc * __gc * byteArray __gc[])
>
> However this is not allowed.
>
> Can anybody help me in how I need to call a C++ managed method passing a
> reference to a byte array that is going to be initialised in the c++
> layer.
>
> Thanks
>[/color]