Unable to use C++ dll in the windows phone 8 application.

Question

Hi folks,

I am trying to use the native c++ dll compiled for Win32 platform using PInvoke. The native dll is a simple library which is returns some dummy values of native data types. The dll is working fine with the traditional Windows Forms Applications. But when I am trying to use the same dll in the Windows Phone 8 app, I am getting a runtime exception, "An exception of type 'System.NotSupportedException' occurred in Unknown Module. but was not handled in user code".

 

[System.Runtime.InteropServices.DllImport("win32dll.dll", EntryPoint = "Hello")]
        private static extern int Hello();

As one can see the InteropServices classes in Windows Phone 8 sdk, the PInvoke must be supported! am I going wrong some where? Can some one give me sample windows Phone 8 app project which is using native C++ dll.

Answer 1

You can't run dlls compiled for Windows on an ARM device. 

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Matt Small - Microsoft Escalation Engineer - Forum Moderator
If my reply answers your question, please mark this post as answered.

NOTE: If I ask for code, please provide something that I can drop directly into a project and run (including XAML), or an actual application project. I'm trying to help a lot of people, so I don't have time to figure out weird snippets with undefined objects and unknown namespaces.

Answer 2

Sorry for using the confusing name of the dll.

I already compiled the source code to the ARM architecture and generated the ARM dll. But still same exception is coming!

Answer 3

Here's the official list of InteropServices classes supported by the phone:
http://msdn.microsoft.com/en-us/library/windowsphone/develop/system.runtime.interopservices(v=vs.105).aspx

DllImport isn't one of them.

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Matt Small - Microsoft Escalation Engineer - Forum Moderator
If my reply answers your question, please mark this post as answered.

NOTE: If I ask for code, please provide something that I can drop directly into a project and run (including XAML), or an actual application project. I'm trying to help a lot of people, so I don't have time to figure out weird snippets with undefined objects and unknown namespaces.

Answer 4

Here's the official list of InteropServices classes supported by the phone:
http://msdn.microsoft.com/en-us/library/windowsphone/develop/system.runtime.interopservices(v=vs.105).aspx

DllImport isn't one of them.

Do you mean DllImportAttribute that is clearly listed on that page you linked to?

Answer 5

Is your dll calling a Win32 API that is not in the list of Supported Win32 APIs for Windows Phone 8?

Answer 6

No its not using any Win32 API calls. As mentioned, The native dll is a simple library which is returns some dummy values of native data types. It would be better if any one can post a link where I can download the sample Windows Phone 8 Project which is successfully able to load the unmanaged dynamic link library. I guess there are some issues with importing of unmanaged code, that is why I am not able to find even a single working project which is successfully able to interop unmanaged dll for WP8.

Answer 7

I can see DllImport supported in the official list pointed by the above link!!

Answer 8

The dll is working on the following platforms except Windows Phone 8:

• Windows Forms Application / .Net Framework
• Windows Store Apps

However, The unmanaged code is working now in windows phone 8 this way:

• Compile the c++ source code as .Lib/.h files
• Create a Window Phone Runtime Component Wrapper
• Add the assembly to the reference in the Windows Phone Application

I suppose one has to rely on Windows Runtime Component till the DllImport issue gets fixed in Windows Phone 8.

Answer 9

That's right.  I remember now.  Interop is broken on Windows Phone 8.  That's why SharpDX had to create a small C++ WinPRT component to interop with DirectX.  Microsoft have admitted that interop was broken and that it will be fixed in a future release.

Answer 10

Yes - sorry I wasn't thinking clearly that it was an attribute - I was looking for method names.  My apologies.

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Matt Small - Microsoft Escalation Engineer - Forum Moderator
If my reply answers your question, please mark this post as answered.

NOTE: If I ask for code, please provide something that I can drop directly into a project and run (including XAML), or an actual application project. I'm trying to help a lot of people, so I don't have time to figure out weird snippets with undefined objects and unknown namespaces.