convert to double *

[Sagiv]

How could I pass a double* argument form my C# application to C++ assembly code which has the following prototype
void abc(double * a, int nArgs

...
Thanks

[BMermuys]

Hi,
"Sagiv" <an*******@discussions.microsoft.com> wrote in message
news:7F**********************************@microsof t.com...

How could I pass a double* argument form my C# application to C++ assembly code which has the following prototype: void abc(double * a, int nArgs)
{
...
}
If "a" is an array :

[ImportDll("...")]
public static void abc([In,Out]double[] a, int nArgs);

The callee can change the array, but it cannot change the size and to access
the array safely the callee should know the size, maybe trough nArgs.

Otherwise:

[ImportDll("...")]
public static void abc( ref double a, int nArgs );

hth,
greetings


Thanks,

[Sagiv]

Hi,
Thanks, in my case it's not a dll which I call, but a managed C++ code, therefore I have to call it directly
Is there a way to pass an argument from C# which is of type double *

Thanks a lot for your reply
Sagiv

[BMermuys]

"Sagiv" <an*******@discussions.microsoft.com> wrote in message
news:4A**********************************@microsof t.com...

Hi,
Thanks, in my case it's not a dll which I call, but a managed C++ code, therefore I have to call it directly. Is there a way to pass an argument from C# which is of type double * ?
No, double* isn't managed.

void abc(double __gc * a, int nArgs)
void abc(double __gc & a, int nArgs)
void abc(System::Double * a, int nArgs)
void abc(System::Double & a, int nArgs)

These functions are all valid mc and the 'a' parameter would be a 'ref
double' in c#.

hth,
greetings


Thanks a lot for your reply.
Sagiv.

[codymanix]

> Thanks, in my case it's not a dll which I call, but a managed C++ code,
therefore I have to call it directly.

Is there a way to pass an argument from C# which is of type double * ?

What do you mean with directly? You cannot call code from an .exe or a .obj
file. You must compiler your c++ code into a dll, exporting the functions
you want to cann from your C# app.

If you are using managed C++, you can simply add your C++ project in your
workspace and call it exactly as you would call your C# stuff. Don't forget
to add the project reference to the c++ project in your c# project.

--
cody

Freeware Tools, Games and Humour
http://www.deutronium.de.vu || http://www.deutronium.tk

[codymanix]

> Thanks, in my case it's not a dll which I call, but a managed C++ code,
therefore I have to call it directly.

Is there a way to pass an argument from C# which is of type double * ?

What do you mean with directly? You cannot call code from an .exe or a .obj
file. You must compiler your c++ code into a dll, exporting the functions
you want to cann from your C# app.

If you are using managed C++, you can simply add your C++ project in your
workspace and call it exactly as you would call your C# stuff. Don't forget
to add the project reference to the c++ project in your c# project.

--
cody

Freeware Tools, Games and Humour
http://www.deutronium.de.vu || http://www.deutronium.tk

[Mattias Sjögren]

Is there a way to pass an argument from C# which is of type double * ?

Yes, in an unsafe code block

double d = 123.45;
unsafe {
yourMCPPObject.YourMethod( &d );
}

Mattias

--
Mattias Sjögren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
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