I'm currently dealing with a part-time (and annoying) bug with some extension methods in VB .NET (VS 2010 and VS 2008).
I have some client projects that use some extension methods from a "Framework" Project I created for general purpose.
However, sometime, when a try to start the solution, I get a long list of error saying the extension method "is not a member of" target object.
When this happen, I can rebuild the solution without getting any error but if I start the project again, the same error will be raised again.
So far I have 2 workaround
A) Go on the extension method definition, delete the tag, compile (with error), put the tag back.
B) Close Visual Studio et re-open it.
Is there any betterway to handle this problem?
There is an active bug report for this problem at Connect. There's a dire need for a repro, a project with specific steps to let them reproduce the issue in-house. Perhaps you can help, it's what it will take to solve it or recommend a workaround.
EDIT: one late addition to this answer, since I've posted this there have been additional questions that note a problem with the IntelliSense parser behaving different from the compiler. There's an issue with the multi-targeting feature, particularly in VS2010, triggered by the Client Profile option for .NET 4. It is the default for a new project. What goes wrong is adding an assembly reference that requires the full profile, commonly because of a dependency on System.Web. You'll get a warning for that, but that's quickly blown away with a large number of errors. The fix is to change the project's Framework Target from client to full.
I've recently encountered this same issue. My project would Build just fine but if I tried to use the Rebuilt option I would get the error about my extension methods not being found on the objects they were extending.
I have managed to fix this today by including an Import at the top of the classes using the Extension method.
So at the top of the file I actually have
Imports project_name.extension_module
I have no idea why this is required but it fixes the problem in my case. I hope this helps somebody else that has wasted as much time with this as I have!
Liam
A less time consuming work around than the two you listed is to "Rebuild Solution" instead of the normal Build Solution. This has always worked for me whenever I run into this problem.
We have something very similar. Call extensions merhod that extends type A. type is actually an instance of type B that implements interface C. interface C has a method with the same name as extension method.
Interface C declares method Foo
Class B inherits from A implements C
Static Class
Static method Foo (this A)
If A is C
(A as C).Foo
When debugging on the line if A is C it actually calls Foo multiple times and you can step at assembly level and see it indicates it is doing the comparison. The way we demonstrate that the call is happen Foo executes a sql statement and we can see sql profiler executing the code in Foo.
Change A as C to reflection and bug goes away. Or use debugger hidden/step through and bug is masked. Also if you micro-step the sql profiler shows the query is getting called multiple times (before Foo is actually called) for each assembly statement.
Related
I'm trying to port my console app over to a Blazor app. Everything worked fine inside the console type project, but it's not inside the Blazor project so I'm trying to troubleshoot. The app calls some things from a separate "class library" type project within the same solution.
The troubleshooting process itself is having issues of its own though. After a little bit of confusion I realized that the breakpoints set inside the referenced class library type project's code are not being hit.
Checking to console, I see it gives the error:
L: Unable to insert breakpoint at FtxApi.FtxWebSocketApi/<Test>d__5:MoveNext ():15
Is there anything I need to do (project settings or something) for the debugger to hit these? Or is it not supported at the moment?
Right now I'm just using a lot of Console.Writeline sort of as a workaround/replacement. And I noticed that the Console.Writelines inside the referenced class library type project are being called.. but only up to a certain method call that comes from a third party package. Execution seems to return from that point (nothing is called after it). Not sure what's going wrong there - more troubleshooting is needed, which brings us back to the breakpoints not firing (ideally I'd be able to make use of them).
I understand Blazor is new (and I'm an absolute beginner at using it), so not everything needs or is going to be perfect. I'm asking about the breakpoints kind of out of curiosity (I'd like to get them working but no big deal otherwise).
What I'd really like some insight into is: What might be going on with the code seemingly stopping execution / returning at that one particular method call? The method I'm calling is WebSocket.Open(), from the package WebSocket4Net. As mentioned above, I've tested this before (in a Console app) and it worked fine, so I'm guessing it's somehow related to Blazor which I'm unfamiliar with. I'm unsure how to get any more info to help debug this problem. Any help appreciated.
Edit:
I managed to find a solution to my problem without the use of debugging tools like breakpoints and such (I just used Console.Writeline a lot). I guess Blazor does not support some websocket implementations or something, because I found this error: System.PlatformNotSupportedException: Operation is not supported on this platform. blazor.webassembly.js:1 at System.Net.Sockets.Socket coming from websocket.Open(). I managed to get it working by implementing System.Net.Websockets instead, similar to this. Though my troubleshooting is over (for now), I'm still wondering if it's somehow possible to use breakpoints inside other referenced projects.
There are 2 solutions:
Solution 1: Right-click at Solution, choose Properties, choose Common Properties, Choose Multiple startup project, choose Action Start for Foo.Client, Foo.Server, Foo.Shared . Something like this
See https://blog.magnetismsolutions.com/blog/paulnieuwelaar/2015/04/07/debug-multiple-projects-at-the-same-time-in-visual-studio
Solution 2: Compile SharedProject, attacht PDB for debugging.
https://learn.microsoft.com/en-us/visualstudio/debugger/how-to-debug-an-executable-not-part-of-a-visual-studio-solution?view=vs-2019
With the risk to fall into too specific question...
Given a C++ MFC (mixed, not shaked) project compiled with /CLR, I have 200 classes already defined.
When I add a new empty class to this project, an error raises when I compile and execute in debug mode.
An unhandled exception of type 'System.IO.FileLoadException' occurred
in Unknown Module.
Additional information: Could not load file or assembly 'ProjectA,
Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' or one of its
dependencies. Could not find or load a type. (Exception from HRESULT:
0x80131522)
ProjectA is the name of the MFC project itself. There is no reference to any ProjectA assembly on project configuration, and there is no reference to another custom assembly.
This project only have references to some .NET Framework assemblies, in order to allow that some of custom defined classes in the project can use CLR classes.
Then, the question is...
Do you know whether there is any limitation of class number on a MFC C++ project?
EDIT:
As I say in comments, in release mode the compilation succeed without errors.
Also, I clean, build, clean, close Visual Studio, reboot computer... and the problem still appears.
If I keep in 200 classes, there is no error. When I go to 201, the error appears.
Currently I'm trying to reproduce in a new default MFC project, adding classes till arrive to 200, to confirm that there is a real limitation.
EDIT 2: ERROR FIXED
Great. #MSX and #frymode show me how avoid the error with his comments.
In the Visual Studio development environment (source / source):
Open the project's Property Pages dialog box.
Click the C/C++ folder.
Click the Code Generation property page.
Modify the Enable String Pooling (/GF) property.
Thank you guys!
The /GF hack is a known workaround for this problem. It is however not a correct one, you are putting a band-aid on a heavily bleeding wound. Pretty important that you heal the problem instead of putting a patch on it, this heavily affects the way your program runs at runtime as well.
The problem maker is the <Module> class, an internal class that the C++/CLI compiler generates. You can see it with ildasm.exe or a good decompiler. This class is required as a home for declarations in your program that are not class members, valid in native C++ but not supported by the CLR. Which demands that every variable or function declaration is a member of a class. The C++/CLI compiler solves it by moving such a declaration into the <Module> class.
There is however a limit on the number of members in a class, they are represented in the metadata of the .NET assembly with a metadata token. An index into other tables. The upper byte identifies the table number, the lower bytes are the index in the table.
You exceeded that limit. This is bad.
A problem with the /clr compile option is that it works too well. It is capable of compiling any C++03 compliant native C++ code to MSIL. Such code will be just-in-time compiled to machine code by the jitter, just like normal managed code. It is however not verifiable code and it doesn't act like managed code at all, you can blow up your program with pointer fumbles just as easily. And above all, it is not code that's optimized with the native C++ back-end. Only the jitter optimizer has a shot at improving that code, it cannot do nearly the quality job that the native C++ optimizer can do, given that it runs with a hard upper limit on how much time it can spend on doing that job.
Have a look-see with a decompiler to see what ended up in that <Module> class. That's going to be overwheliming at first, you know you've got a big one right now. You fix this problem by spending more time segregating the code into the managed parts and the native parts. Where the native code should be compiled without /clr in effect. It is a per-source file setting, you can even switch back-and-forth in a single source code file with #pragma managed. The simplest way to segregate is by keeping your native code in its own library or DLL.
This link shows that there's no limit to the number of types you can have in a namespace (not a project). Considering, that a namespace can be split across different assemblies, you could, at least in theory, have an unlimited number of types. However, this post affirms that the maximum number of classes in a .DLL
is 16777215. Probably, you'll run out of memory before you reach that number of classes :)
Just for information: there seems to be a limit to the number of fields per class, though.
P.S.:
Here's the solution to your problem taken from this link
Open the project's Property Pages dialog box.
Click the C/C++ folder.
Click the Code Generation property page.
Modify the Enable String Pooling property.
When dynamically referencing assemblies in .fsx using #I and #r, VS highlights the following usages of imported types and writes "The namespace or module 'XXX' is not defined". Is it ok?
For example, in the following code
#I #".\Tools\FAKE"
#r "FakeLib.dll"
open Fake
Target "Hello" (fun _ -> trace "hello!")
Run "Hello"
VS highlights Fake and says "The namespace or module 'Fake' is not defined", it also highlights Target and Run. I have this problem in VS 2010 SP1 and in VS 11 CTP. This issue makes writing F# scripts a bit harder task than it could be.
By the way, IntelliSence for "common" types works well. FakeLib.dll and FakeLib.xml are present in the .\Tools\FAKE directory. The code runs well.
Update 1
Here's the screenshot of the situation. You can see that VS resolves assembly FakeLib correctly (in a tooltip), and that at the same time Intellisense "see" standard types (tooltip over Console) class.
Update 2
I think there's something wrong with the IntelliSense on my work workstation, because it (IntelliSense) behaves itself quite strange. When I start VS and open .fsx file, IntelliSense refuses to resolve even standard types/classes, and it doesn't underlines FAKE classes, it does nothing. But after some period of time and some manipulation over code IntelliSense starts working for standard types and underlines FAKE types.
Moreover, when I've created the similar code on my home workstation there were no problems, IntelliSense works as it should.
If you put the full path into the #r directive, you'll get full IntelliSense. The #I directive, while convenient, prevents IntelliSense from working properly though the code will run just fine. This is true for both loose scripts and those found in projects. Have a look at Tomas Petricek's [FSharp.AsyncExtensions](http://github.com/tpetricek/FSharp.AsyncExtensions] project.
No, that's not how it works. Does your code run? Intellisense is provided for assemblies referenced using #r.
I recently added a new project to my Visual Studio 2008 solution. Now, as I make edits in the new project, I receive a ton (~50) of type checking errors - indicating that an assembly reference may be missing. However, when I actually build the solution, the errors go away. As best I can tell, my dependencies are set and the build order is correct. What could be wrong?
It doesn't prevent me from building and deploying, but it's a major nuisance. It makes it hard to tell when I actually have introduced new errors (until I do compile). Thus, it erodes the usefulness of having the error window do static analysis.
Example, one of the 50 errors is this:
"The type of namespace name 'PersonManager' does not exist in the namespace 'Gideon' (are you missing an assembly reference?"
In reference to this line of code:
Gideon.PersonManager pm = new Gideon.PersonManager()
PersonManager is underlined in both places, and when I right click the type and selected 'find all references' I get an alert box that says "Cannot navigate to PersonManager"
However, the references are definitely there, because when I build, it works.
One other detail is that there is a mixture of C# and VB.net code, though I don't think that should make a difference.
Well, yes, the IntelliSense parser is not an exact replica of the C# compiler. It has a very different job to do, it needs to do something meaningful while the code is utterly broken since you are editing it. Tough assignment, they did a tremendous job with it. But as a side-effect, it can fail to parse things that are actually legal. It's quite rare but not unheard of, seen it myself a few times.
This won't go anywhere concrete until you at least give us some idea of what kind of errors you are seeing, along with a snippet of the code that generates them. You didn't do so, I can only recommend that you select another window so you don't have to look at them.
I had the same problem. I had a project in my solution that was causing the problem - I removed the project from the solution, then added a reference to that project in the main solution and the errors went away. Strange that it only happened on 1 machine. Opening the solution on another machine was fine...
I'm using VS 2008 Developer Edition and am finding some bugs with the Test Projects.
I am getting one error that doesn't make sense - I have a class called 'Foo' which I need to test and created the blank test class automatically.
Foo takes 3 paremeters in its constructor - IBar, IBaz, IBang.
When I write a test case, I will Dim foo as New Foo(bar,baz,bang), and I will sometimes get an error that says = 'Type IBang could not be implicitly converted to IBang'. This error does not make any sense.
Even more odd - if I switch to an instance of Foo_Accessor() instead, the error goes away. I've played with the references and then I can eventually fix the above error - but then I get the same error for my Foo_Accessor() class!
I clean, rebuild, and sometimes the error will go away - but then I get the error 'Foo_Accessor' is not defined. Now I go to the Foo class and do 'create accessor' again - again, it still gives the same error. So at this point I'm stuck and my solution won't compile, and the only thing I did was add a new test case through visual studio!
Has anyone seen these issues and could please help?
Also - I have tried everything, including instructions from MS such as - renaming the type, re-referencing the project / in different ways, unloading the projects, etc, etc.. still I wind up with either the 'ifoo cannot convert to ifoo' bug or Foo_Accessor is not defined bug... I'm about to just break down and give the damned property I have to check a ReadOnly accessor... !
It's hard to say for certain but it sounds like you have a problem with your references being setup incorrectly. What's likely happening here is that one of the references between your projects is setup as a DLL reference vs. a project reference. This can confuse the type system into thinking that Bang from the project and Bang from the DLL are actually different types.
I would delete all references between my projects. Then go add all of them back again being careful to select the project from the project tab of the add reference dialog vs. the Browse one. This should fix your problem.
Is this a multi-language project or just a single language project? I've found this type of problem is more likely to occur in a multi-language project but it's certainly happened in a single language one.