473,786 Members | 2,405 Online
Bytes | Software Development & Data Engineering Community
+ Post

Home Posts Topics Members FAQ

Marshal SafeArray as array<T>

Hi all,
I need to implement an unmanaged function that gets a SafeArray and
hands it over to a managed function having the managed array-type.
Using MarshalAs I can call unmanaged functions having SafeArray from
managed code. But here I need this vice-versa...

I assume it is doable with MarshalAs magic, but how?

Thanks
Christian

example:

ref class Funcs {
static double mysum(array<dou ble>^ arr) {
double sum = 0;
for each(double x in arr) sum += x;
return sum;
}
};

extern "C" {
double WINAPI mysum(SAFEARRAY ** arr) {
// ERROR - need some MarshalAs magic
return Funcs::mysum(ar r);
}
}
Jul 9 '07 #1
1 2833
"Christian Schmidt" <no**@locom.dew rote in message
news:uR******** ********@TK2MSF TNGP03.phx.gbl. ..
Hi all,
I need to implement an unmanaged function that gets a SafeArray and hands
it over to a managed function having the managed array-type.
Using MarshalAs I can call unmanaged functions having SafeArray from
managed code. But here I need this vice-versa...

I assume it is doable with MarshalAs magic, but how?
It's not. A managed array must be on the managed heap. The only way to get
the data onto the managed heap is to copy it.

-cd
Jul 10 '07 #2

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

Similar topics

1
1921
by: herrcho | last post by:
#include <stdio.h> int multi; int main() { printf("\nmulti = %u",multi); printf("\nmulti = %u",multi); printf("\n&multi = %u\n",&multi); return 0;
8
1569
by: Greenhorn | last post by:
Hi, Those relational operators have operands of all numerical type int,char,float etc. They also are working for character arrays. Whats the logic behind their working. Is the length of the array compared first and then each character compared with corresponding character. { const char msg = "msessage}", ch = "Za";
24
17490
by: Marcus Kwok | last post by:
Hello, I am working on cleaning up some code that I inherited and was wondering if there is anything wrong with my function. I am fairly proficient in standard C++ but I am pretty new to the .NET managed C++. It seems to work fine, but everyone knows that programs with errors can still appear to "work fine" :) I am working with VS .NET 2003; I am unable to upgrade to 2005 at this time, so I cannot use the newer syntax or features. ...
9
3688
by: Simple Simon | last post by:
Java longs are 8 bytes. I have a Java long that is coming in from the network, and that represents milliseconds since Epoch (Jan 1 1970 00:00:00). I'm having trouble understanding how to get it into a struct timeval object. I get the ByteBuffer as an array of const unsigned char, 'buffer'. Here's an example: 00 00 01 0A 29 1D 07 E4 This value maps somehow to Thu Mar 23 16:57:49 2006 and some
1
2343
by: kenneth6 | last post by:
1. In C++/MFC, if I pre-import the binary bitmap into the resource first, then how can I save the bitmap element values to 2D array as 1 and 0 ?? 2. In C++/MFC, If I have a 2D array containing 1 and 0, how can I export the array to display a binary image on the windows dialog screen?? (Or where can I find the tuturial or examples about these two questions??)
8
1587
by: Francisco | last post by:
Hello, Is there any code faster than this array position manipulation (some code omitted for brevity)?: internal struct TreeNodeTableItem { public int a; public int b; public int c; public int d;
0
9492
by: Hystou | last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can effortlessly switch the default language on Windows 10 without reinstalling. I'll walk you through it. First, let's disable language synchronization. With a Microsoft account, language settings sync across devices. To prevent any complications,...
0
10360
Oralloy
by: Oralloy | last post by:
Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers, it seems that the internal comparison operator "<=>" tries to promote arguments from unsigned to signed. This is as boiled down as I can make it. Here is my compilation command: g++-12 -std=c++20 -Wnarrowing bit_field.cpp Here is the code in...
0
10163
jinu1996
by: jinu1996 | last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven tapestry of website design and digital marketing. It's not merely about having a website; it's about crafting an immersive digital experience that captivates audiences and drives business growth. The Art of Business Website Design Your website is...
1
10108
by: Hystou | last post by:
Overview: Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
0
8988
agi2029
by: agi2029 | last post by:
Let's talk about the concept of autonomous AI software engineers and no-code agents. These AIs are designed to manage the entire lifecycle of a software development project—planning, coding, testing, and deployment—without human intervention. Imagine an AI that can take a project description, break it down, write the code, debug it, and then launch it, all on its own.... Now, this would greatly impact the work of software developers. The idea...
1
7510
isladogs
by: isladogs | last post by:
The next Access Europe User Group meeting will be on Wednesday 1 May 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM). In this session, we are pleased to welcome a new presenter, Adolph Dupré who will be discussing some powerful techniques for using class modules. He will explain when you may want to use classes instead of User Defined Types (UDT). For example, to manage the data in unbound forms. Adolph will...
0
6744
by: conductexam | last post by:
I have .net C# application in which I am extracting data from word file and save it in database particularly. To store word all data as it is I am converting the whole word file firstly in HTML and then checking html paragraph one by one. At the time of converting from word file to html my equations which are in the word document file was convert into image. Globals.ThisAddIn.Application.ActiveDocument.Select();...
0
5532
by: adsilva | last post by:
A Windows Forms form does not have the event Unload, like VB6. What one acts like?
2
3668
muto222
by: muto222 | last post by:
How can i add a mobile payment intergratation into php mysql website.

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.