473,320 Members | 1,821 Online
Bytes | Software Development & Data Engineering Community
Post Job

Home Posts Topics Members FAQ

Join Bytes to post your question to a community of 473,320 software developers and data experts.

convert to double *

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

Nov 16 '05 #1
6 2953
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,

Nov 16 '05 #2
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

Nov 16 '05 #3

"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.

Nov 16 '05 #4
> 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
Nov 16 '05 #5
> 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
Nov 16 '05 #6
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
Please reply only to the newsgroup.
Nov 16 '05 #7

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

4
by: cindy liu | last post by:
Hi, In .Net, how to convert a string to a double? Thanks in advance! Cindy
12
by: Sydex | last post by:
When I compile code I get error C2664: 'Integration::qgaus' : cannot convert parameter 1 from 'double (double)' to 'double (__cdecl *)(double)' in this part : double Integration::quad2d(double...
2
by: Pascal | last post by:
Why does this not work, and how should i do this convert in stead: string x = double.MinValue.ToString(); double y = Convert.ToDouble(x); i get this exception: An unhandled exception of type...
1
by: Sam | last post by:
How do I convert Julian Date to Calendar Date in ASP.Net 1.1 based on following guideline found at Internet? To convert Julian date to Gregorian date: double JD = 2299160.5; double Z =...
4
by: Daniel Walzenbach | last post by:
Hi, I wonder if somebody could explain me the difference between Double.Parse and Convert.ToDouble. If I'm not mistaken they are implemented differently (I though for a moment they might be the same...
17
by: David Scemama | last post by:
Hi, I'm writing a program using VB.NET that needs to communicate with a DOS Pascal program than cannot be modified. The communication channel is through some file databases, and I have a huge...
3
by: Eric BOUXIROT | last post by:
hi, i must convert all of these eVC++ prototypes to use with VB.NET.... DLLEXPORT long F_BDO_MessageBoxOK(char *IN_title, char *IN_msg ); DLLEXPORT long F_BDO_MessageBoxOUINON(char *IN_title,...
3
by: PeterK | last post by:
I am trying to set Public overridable CreditlimitS() as System.Data.SqlTypes.SqlMoney to Creditlimit as Double like CreditLimitS=creditlimit and get this error "Value of type double cannot be...
4
by: Edwin Knoppert | last post by:
In my code i use the text from a textbox and convert it to a double value. I was using Convert.ToDouble() but i'm used to convert comma to dot. This way i can assure the text is correct. However...
3
by: mrajanikrishna | last post by:
Hi Friends, I am accepting a number from the user entered in a textbox. I want to assign to a variable in my code and assignt this to that variable. double num1 = (double)txtNum1.text; ...
0
by: DolphinDB | last post by:
Tired of spending countless mintues downsampling your data? Look no further! In this article, you’ll learn how to efficiently downsample 6.48 billion high-frequency records to 61 million...
0
by: ryjfgjl | last post by:
ExcelToDatabase: batch import excel into database automatically...
0
isladogs
by: isladogs | last post by:
The next Access Europe meeting will be on Wednesday 6 Mar 2024 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM). In this month's session, we are pleased to welcome back...
1
isladogs
by: isladogs | last post by:
The next Access Europe meeting will be on Wednesday 6 Mar 2024 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM). In this month's session, we are pleased to welcome back...
0
by: jfyes | last post by:
As a hardware engineer, after seeing that CEIWEI recently released a new tool for Modbus RTU Over TCP/UDP filtering and monitoring, I actively went to its official website to take a look. It turned...
1
by: PapaRatzi | last post by:
Hello, I am teaching myself MS Access forms design and Visual Basic. I've created a table to capture a list of Top 30 singles and forms to capture new entries. The final step is a form (unbound)...
0
by: Defcon1945 | last post by:
I'm trying to learn Python using Pycharm but import shutil doesn't work
0
by: af34tf | last post by:
Hi Guys, I have a domain whose name is BytesLimited.com, and I want to sell it. Does anyone know about platforms that allow me to list my domain in auction for free. Thank you
0
by: Faith0G | last post by:
I am starting a new it consulting business and it's been a while since I setup a new website. Is wordpress still the best web based software for hosting a 5 page website? The webpages will be...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.