I have a C++ solution. The startup project is an exe. In the solution there are a number C# dlls (targeting .NET Framework 2.0) that are registered for COM interop. When I put a breakpoint in the C# code I get the hollow red breakpoint with "No native symbols in symbol file"
I have tried setting Project Property Pages -> Debugging -> Debugger Type to Mixed on the start-up project that calls the COM methods.
I have checked Debug -> Windows -> Modules. It has loaded my dlls, and the symbol status is "No native symbols in symbol file".
This is not the end of the world because if I do Debug -> Start Without Debugging and then Debug -> Attach to Process, changing the Attach To: to Managed (v2.0, v1.1, v1.0) code, Native code. Then I hit breakpoints in both the C++ code and C# code.
So I have my workaround but I reckon if I can do it by attaching to process - I should be able to do it by just debugging.
How can I hit my C# breakpoints by just doing Debug -> Start Debugging?
I was able to debug my C# dll from a C++ project in VS2008 by doing the following:
In the C++ project's properties, goto Configuration Properties -> Debugging. Set "Debugger Type" to Mixed. "Attach" should be set to No.
In your C# project properties, in the Debug tab, set the "Start External Program" to your C++ project's executable.
I know it's a little bit old but I found a practical solution for the problem.
I had the same problem while using a C++ application which uses a C# COM-Object. I tried several settings within Visual Studio on the C++ and C# side. Nothing helps until I tried manually launching the Debugger.
You can use
Debugger.Launch();
to manually start the Debugger on your C# DLL. I know this is not the best but a practical way. In later productive environments you have to remove the Debugger launch function :).
Regards
I am unsure if this will help but we work a lot with C# and C++. I found this to be possible by placing the C++ project and the C# project in the same solution and enabling "native debugging" in the C# project. Then I was able to jump back and forth between them while debugging.
Related
I'm trying to debug a C# dll from a native C++ executable. I have a C# COM object that is loaded and run from native code via IDispatch. Everything is built in Debug, both C# and C++ code. Whilst I can see all the c++ code, and all the c++ dlls have their symbols loaded and available for debugging, breakpoints etc the C# code refuses to play.
What I do see is that the C# dlls all refuse to load their symbol pdbs, reporting "skipped loading symbols for ngen binary" in the modules window.
Incidentally, I am debugging the C# solution here, I have set the native executable as the 'start external program' in the COM project's debug settings.
Now I can start the C++ executable and then attach to it, and then all works as I expect - the symbols load and I can set breakpoints in the C#.
This is using Visual Studio 2013u4. Is there a setting to enable mixed-mode debugging? One niggle is that the native code was built with VS2010.
Here's the Module window - note all pdbs and dlls are in a single directory, you can see the c++ dlls loaded, but not the C# ones.
Here's the modules window - note the 3rd entry for the EvCom dll (the COM object) which I assume is the entry enabling debugging.
There is nothing of any interest in the Output window, when it comes to load the COM dll, I see the following (in the case of attach to running process, the other only has 2 Loaded lines instead of 3).
'Explorer.exe' (Win32): Loaded 'C:\Dev\...\lib\debug\EvCom.dll'.
'Explorer.exe' (Win32): Loaded 'C:\Dev\...\lib\debug\EvCom.dll'.
'Explorer.exe' (Win32): Unloaded 'C:\...\lib\debug\EvCom.dll'
'Explorer.exe' (Win32): Loaded 'C:\Dev\...\lib\debug\EvCom.dll'.
One thing of interest - I checked the "Use Managed Compatibility Mode" in the debug settings and, thought it still doesn't load my symbols when starting debugging, it only shows 1 entry in the modules list. This time saying "No native symbols in symbol file" for the C# dlls.
It looks like the problem is not being able to select the debugger type in VS2013 (or 2012). This connect article suggests its "by design" with some workarounds.
Turns out it is all down to the changes in debug engine for .NET 4.0
.NET 4 and greater uses a different debug engine than .net 3.5 and below, when you start debugging a native application the debugger will choose a .net debugger for you (defaults to .net 4.0) and if your .net dll is built using this platform, all will be well - breakpoints will be hit.
If your loaded dll is .net 3.5, then the debug engine will not understand the dlls that are loaded and will refuse to load symbols or debug.
The solutions are either to rebuild as .net 4, or start the native executable and attach to it (where you can select the debugger type, either 'old' .net or 'new' .net) or you can create a project from the executable and set its debug settings to specify the right debugger.
What I find annoying is that Microsoft could easily have started the debugger using the .NET framework type specified in the project you're debugging (after all, when debugging a dll and specifying an external program, you still want to debug the dll you're pressing F5 for, so you know what debugger to use!)(What is even more annoying is that once managed debugging is started in a loaded dll, you can then step into projects built using older .net frameworks without problem).
More details on this Microsoft connect article
(If your executable isn't already in your solution, File > Add > Existing project, then right-click and set it as start-up project.)
Right-click your start-up project, Properties, Debugging, Debugger Type = Mixed.
In my case I have own symbol server and TFS, so I
enabled option TOOLS > Options > Debugging > General > "Enable source server support" and three child options.
For me is was debugging a UWP app in Xamarin Forms:
Cause:
The debugger is skipping files not in the .NET environment.
Solution:
Uncheck Debugging => General => Enable Just My Code
I have been stump in this problem for a few hours now. I hope someone has had a similar problem to this.
We have developed a prototype .Net(C#) dll using VS2010, and would like to be able to call this dll in a both C# applications and VB6 application.
My question is:
Is it possible to debug a VB6 application that is calling a .Net dll? I get an error message "Automation Error The system cannot find the file specified"
The error message suggests that there is something missing for my VB6 app to find the .Net dll.
I am aware that if the VB6 application has been compiled, and the .exe has been created, the VB6 will successfully call the .Net dll functionality when using the .exe
However it is important that we can debug through our VB6 application. Unfortunately debugging does not allow you to step over the line of code instantiating the .Net DLL's class object. I can't seem to do this.
NOTE: I have looked around forums and MSDN documentation and I mostly find solution for calling a VB6 dll in .NET; which is unfortunately the opposite of what we need to do.
NOTE: I have already registered the compiled .Net(C#) assembly, and referenced it in the VB6 project.
I have however found these two pages, which seemed to be what we need, but its a solution for calling a .NET(c#) dll generated using VS2005. This doesnt seem to work when the .NET(C#) dll was generated using VS2010.
site1
site2
If someone could give any suggestions or direct me somewhere I can get one, that would be great.
Thanks
SOLUTION
Thanks to #HansPassant, I have found the solution.
To debug a VB6 project that contains a C# .NET assembly, you need to register the .NET dll through both "regasm" and "gacutil", then make sure to close and reopen the VB6 application before you start debugging.
This is not a problem, VB6 uses its own debugger that doesn't get in the way of any other debugger, including the managed one for C# code.
You start from your C# class library project, ensure it is selected as the start project. Project + Properties, Debug tab. Select the "Start external program" option and enter the path to the VB6 IDE. Typically c:\program files\microsoft visual studio\vb98\vb6.exe. Set a breakpoint on the method you want to debug.
Press F5 and the VB6 ide will start running. Load or create your vb6 project. Note how you can add the path to the .vbp project in the previous step so it will automatically load your project.
Start debugging your vb6 project as usual. As soon as it starts using your [ComVisible] C# class then your C# assembly gets loaded. And the breakpoint will hit when your vb6 code calls the method. Switch back and forth as needed. Note that you cannot single-step from vb6 to C# code, you have to set breakpoints to get the debugger to stop.
Ah, the wonders of using .NET from VB6 in a debuggable manner.
in the VB6 project compile options (reached using the Options button on the Make Project dialog window), choose the Compile to Native Code, No Optimization, and Create Symbolic Debug Info options. Then compile your VB6 project. These options allow proper VB6 binary-to-source mapping.
Go to the Configuration Properties...Debugging property page of your solution and change the Start Action to launch your VB6 executable.
In VS Solution Explorer, go to File...Add Existing Item and navigate to the folder containing the VB6 source code you want to debug. Double-click on the VB6 source code file you want to debug, and a source window should open in VS that allows you to set breakpoints in the VB6 source code.
Make sure that your .NET library has a public default constructor. This is essential.
Now also set any C# breakpoints that you need. Do not step into the .NET code - this doesn't work.
When you start debugging with VS, your VB6 and C# breakpoints should be hit normally.
One approach is to debug each individually:
Debugging the VB6 code can be done in the IDE after compiling the C# DLL and adding it as a reference to the VB6 project.
Debugging the DLL with the VB6 host is possible in Visual Studio by compiling the VB6 project and using it in the project properties as the executable to run.
In some cases this is simpler/quicker than setting up the environment to debug both simultaneously.
This approach will require having at least the framework of each working beforehand.
I have created a visual c++ 6.0 dll project and using it from my c# code. Now i want to debug the dll but i am not able to do it.
I choose the following option to do it:
put the breaking point in my visual c++ project code.
build the dll and copy it into the directory of my c# project.
Now i build my c# project and dll works fine (method are calling perfectly).
Now i want to debug the dll.
I follow a blog and open the c++ project and choose the Attach to process from vc++.
but i am not able to find the running process of visual c# project, whereas it available at task manager process.
In my c# project solution i have two project i.e.
web service (i called the dll method at the time of accessing a url)
Another one is webform application which starts the web services.
Now please help me how should i debug my dll. I have followed so many blogs but all of them are focusing on Attaching process method which is not working in my condition. What should i do?
You'll need to enable unmanaged debugging, it is not turned on by default in either scenario because your main program is managed.
You do it in your C# project with Project > Properties > Debug tab > tick the "Enable unmanaged code debugging" checkbox.
You do it with Tools > Attach to Process by clicking the Select button. Choose the "Debug these code types" radio button and tick both Managed and Native. You may have to resort to only native if your process is 64-bit.
Set a breakpoint in the DLL's source code and be sure to write C# code that exercises the DLL function. If you still have trouble getting a breakpoint then use Debug > Windows > Modules and verify that you see the DLL in the module list. Get additional troubleshooting info by right-clicking it, select Symbol Load Information. Which shows a trace of where the debugger looked for the PDB file.
You can add C++ project to the your C# solution and add reference directly to the project (not dll), then you will not be needing to copy DLL. After that just start normal debugging (F5) of your C# project, and breakpoints will be working for C++ project too. This way will be very comfortable for debugging. I have tried such debugging and did not change any other settings.
I've been writing a program that serves in two primary parts- managed UI and native back-end (C# and C++). However, suddenly, Visual Studio thinks that when I try to run the solution, I'm tryng to run the native back-end (a DLL) and throws an error. When I start the exe manually, it won't break on my breakpoints, and suchlike - even though I've enabled mixed debugging. How can I set it back to the original settings- mixed mode debugging and start the managed .exe when launching? I'm in Visual Studio 2010.
I think that this is probably caused because I had a blue-screen in the middle yesterday, and this is the first serious work I've done on it since.
It sounds like you just need to set the managed project as the startup project in Visual Studio.
Open Solution Explorer
Right click on the project and select "Startup Project"
I have a .dll from c++ and I want to debug it in C#, but I don't know how to.
When I compiled the c++ project, Visual studio asked me to execute an ".exe".
I supposed that I had to create a project to execute the dll.
But I am lost, how could I debug it?
If I understand you correctly, you want to debug a C++ coded DLL that you created, in a C# project that calls the DLL, which you also created?
I've done this before by going into your C# project properties, and under the Debug section, checking the "Enable unmanaged code debugging" check box. This should allow you to step into your C++ DLL.
To debug a C++ from C# there a couple of things you have to do.
Add a C# project to you solution for your debug application.
Edit the properties of the C# project to "Allow unmanaged code debugging" on the "Debug" tab of the project properties.
Set the C++ project as a dependency of the C# project.
Write code in your C# project to use the DLL either using P/Invoke or COM.
Set some breakpoints in your C++ code and run the C# project.
I overcame this in Visual Studio 2019 by selecting "Enable native code debugging" as shown under my C# project's properies.
Visual Studio cannot execute a dll on its own.
You need to set the startup .exe that will be using your C++ dll in the properties of your dll project. You can do so from properties --> debugging --> command specifying the path of the executable that's gonna call your dll and any command line argument needed.
For VS 2017 Pro, go to the property page of the main project (your c# project in the solution) by right mouse clicking it. At the Debug menu item, find the option in Debugger engines, choose Enable native code debugging.
To complement the useful answers by heavyd and CCicotta and Noobie3001, in Visual Studio 2017 I also had to change the following when attaching to a running C# process calling a C++ DLL: in Debug > Attach to process ..., ensure Native code is listed by Attach to:
SOS (Son of Strike) Debugging Extension (SOS.dll) helps you debug
managed code in Visual Studio by providing information about the
internal CLR environment
refer the below article:-
MSDN ARTICLE
The option "Allow unmanaged code debugging" in the "Debug" tab works for most people, but it doesn't work for me. I have to manually select "Native" as the following to debug c++ dll in my c# code.
FYI: I'm using vs2019, and the dll is written with c++ and loaded into C# app with "dllimport".