My C# WinForms solution has two projects.
A DLL which is the main project I'm working on, and an executable WinForms I call "Sandbox" so that I can compile/run/debug the DLL easily in one go.
I'm working in .Net 4.0 for both projects.
Everything was working fine until I added some seemingly innocent code, and a reference to System.Web in the DLL.
Now my Sandbox project can't see the namespace of the DLL project. I didn't change anything which I believe should have affected this.
If I delete the project reference to the DLL from the Sandbox references and re-add it, then the red underlines all disappear and the colour coding comes back for all my classes etc; but as as soon as I try to build the solution, the whole thing falls apart again.
When I right-click the DLL project in the Sandbox's references and view in object browser, I can see the namespace and all the stuff in there.
I have a feeling this might be some sort of bug?
Is this some sort of VS2010 bug? I had this same issue a few months ago and I could only fix it at the time by making a whole new project and re-importing my files. This time, however, I have a bajillion files and will only do that as a last resort!
Edit:
After panickedly going through and undoing all my changes, trying to find what caused the problems, it seems to be this line:
string url = "http://maps.google.com?q=" + HttpUtility.UrlEncode(address);
If I comment out this line, then I get no namespace errors and the project builds fine. I can't see anything wrong with this line though.
I'm ready to declare this a bug in VS2010, this has bitten way too many programmers already. The fix is easy: Project + Properties, Application tab, change Target Framework to ".NET Framework 4" instead of the Client Profile that is selected by default.
System.Web is not included in the client profile. Having this option in the first place is quite silly, the client profile is only 15% smaller than the full version of .NET 4.0. Having it selected by default is even sillier. But I digress.
UPDATE: mercifully this all got fixed in VS2012. Which no longer makes the client profile the default for a new project. And the client profile got retired completely in .NET 4.5, good riddance.
Check to make sure that both projects are using the non-client profile for their target framework (go to each project's properties to do this).
One possibility is that the target .NET Framework version of the class library is higher than that of the project.
I faced this problem, and I solved it by closing visual studio, reopening visual studio, cleaning and rebuilding the solution. This worked for me. On some other posts, I have read the replies and most of users solved the problem by following this way.
Try building only the project with the Sandbox dll first independently.
Then point your executable project to the required dll and ensure copy local is set to true. in reference settings.
Tthen build the executable project.
Changing the target framework from the ".NET Framweork 4 Client Profile" to ".NET Framework 4" worked for me with a similar problem. I agree that the client profile doesn't seem to have much of an advantage to using it. I seem to get nailed with weird errors that I hunt for until I remember that Visual Studio defaults to the client profile. I guess the moral of the story when getting an error is: if "Rebuild Solution" doesn't work, check the Target framework...
If you tried already doing the Framework change, and still not worked, I hope this works for you (as it did for me): Simply add the necessary references from within your projects. Very obvious but I was doing it wrong until I found what was the issue.
I just had this issue and it turned out to be I had multiple namespaces being used that had the same object name (i.e. business objects had the same names as mvc models);
Fully qualifying the names fixed the issue for me.
Related
I've been googling this all afternoon and I found any number of people ask the question, and all of the place a few people would answer it with the same things, and then there's a dozen comments by the rest of the world and the OP about how those answer don't fix it. So I'm going to include what I've tried here, and if your solution is to do one of the things I've already tried, I'm going to be very sad.
I have a solution in Visual Studio 2019 that has a class library, a wpf application, and a setup project (using the setup project extension). The WPF app also references a bunch of assemblies of course, but one of those is from another project I maintain in a different solution. I copy/paste the compiled dll after I update it from its own project to this one. Nothing tricky, everything works.
The problem is the installer. If I build everything and then build the installer, it produces an MSI as expected. If I right click on the project in Visual Studio and choose "Install", everything is perfect.
The problem is after I make some updates to either of the code projects, I then build both and build the setup project, and again if I right click to install it's perfect. If I run the MSI though, it doesn't always update the target files. If I delete the target files it will create them with the new ones, but it won't overwrite the old ones correctly.
AssemblyVersion and AssemblyFileVersion are both being incremented each time and are being kept in sync with the "Version" property of the setup project. I tested with these extensively, the new installer that isn't working properly 100% has updated dlls in it with correctly updated version numbers.
When I change the "version" of the setup, it asks to change the GUID for the ProductCode. I say yes, it changes the code. I have also tested without doing this and that makes it much worse as we all know.
"RemovePreviousVersions" is set to "true" in the installer project
If I right click the project and choose "Install" it seems to be 100% reliable at upgrading the existing installation.
If I run the MSI directly it seems to be 100% unreliable and never gets it right.
Side note, it does seem to usually but not always get the WPF application upgraded and the other project dll I bring in if I remember to update its version, but the class library (which is referenced by the WPF application) almost never works.
Has anyone got this to work reliably?
For all the people finding this in the future, here's the final word:
The build project can be inconsistent, this is well documented all over the internet as I have above. You're not doing anything wrong - it is just inconsistent.
Stop trying to solve it if it's affecting your project and move on (I've had a dozen projects before this one work just fine). The consensus seems to be to use WiX, but I'm not here to discuss the alternatives. Personally I am going to embark on the WiX learning curve though.
I have two brand new C# .NET Standard libraries. They each have a project reference to an older .NET 3.5 Framework library. Only one of the two have a yellow icon on the reference.
Everything builds and runs fine but the triangle still exists, why?
I would hope they have a better way to report reference issues
than an unlabeled yellow icon.
Not sure if it's your real question. But you can check the Error List window to get details about why yellow icon displays on the References.
Everything builds and runs fine.
For some scenario, the build in VS can succeed although some build warnings occurs. And it will only fail when some build errors exist.
I add reference to ForTest.dll in my project, this assembly is missing or not compatible with current project, then it displays yellow icon in References. Now since in my project, it doesn't call functions from the ForTest.dll, so it won't exactly affect my build process. Then the project builds successfully and runs fine.
I have tried looking at the build log, in detailed mode, for an error
message, but cannot find anything obvious.
When building a solution with several projects, and set the log in Detailed mode, it's easier to get lost in the hundreds of build logs. Since the yellow icon only displays for one project, you can right-click the project=>rebuild to build the project, it makes the message in build log more clear.
Or just use the Error List window as I suggest above to check the warnings and errors instead of hundreds of logs during Trouble-shooting.
In addition: If you can't find any info in Error List window, then maybe the reason why the yellow icon occurs is because VS didn't load the project well. Please try right-click the project=> unload and reload the project in solution explorer. If it persists,close all vs instance and delete the .vs folder in solution directory, and restart vs.
According to Microsoft, these yellow warning signs get added for every new reference and then removed once the reference is successfully added (=assumed guilty until proven innocent). If some yellow warning remains in the solution explorer, VS knows only that that reference is missing, but doesn't know why and can therefore not display a warning message in the Error window.
Not being able to find out why there is a warning sign is very annoying. The problem was reported, but Microsoft's standard response is: "This problem seems not to be requested enough to be resolved, but if you like, you can contribute your own solution."
So if you read so far, can you please go to developercommunity.visualstudio.com: tell me what's wrong with the reference 2 and vote this issue up, telling MS they should indeed fix this.
After spending hours trying to solve a none existing error, I gave up and closed VS. When I started it again, the problem was gone.
These errors also occur when adding a NuGet package that is not compatible with the current .NET (such as .NET Framework app under .NET Standard or .NET Core, or a .NET version such as referencing .NET Framework 4.8 library from an older .NET version).
Check that the package dependency is the same as the project you're working with.
It could also mean that the third party assembly you have on your machine is not registered in the gac and hence not being found. For older projects mostly if I have to hand copy over the dlls, I will then register them with this powershell script in the directory they reside in:
gci *.dll | % { gacutil /i $_.Name }
This error occurs immediately after building the project, I've tried changing the dot net framework from 4.6 to a lesser version it still does the same thing.
Reinstalling visual studio 2015 doesn't still correct this issue.
Did you check your build path under project > properties> build > output ?
Ok, you don't provide a lot of details so I am going to make some assumptions as I have seen this issue before and it can be a bit tricky.
It sounds to me like you have other issues.
You probably have another project being referenced by your main project. This second project is not building. That's what you need to focus on. Try and build only that project first, when that succeeds you can build your main project and this issue won't happen.
The way things work is like this.
You try to build your main project.
The compiler goes to the referenced projects and tries to build those first, if that succeeds then the dlls generated are copied over to the bin folder of the main project.
If my assumptions are incorrect then please edit your question and add all the details you can so we can actually help you.
This is a very frustrating problem. All of a sudden I cannot use referenced DLLs. I added an assembly reference to a project in the same solution and the namespace is unrecognised. I can even see the reference in the object viewer. I've also changed the projects to .NET 4 and 3.5 without the client profile to no avail.
Based on your screenshot, you have references to the same "ServerLibrary" DLL in multiple projects, however, it looks like one referenced version is compiled in .NET 3.5 and the other referenced version (the project reference it appears), is compiled in .NET 4. Make sure all projects point to the same version of the DLL and recompile all. That should fix your problem.
I faced this problem, and I solved it by closing visual studio, reopening visual studio, cleaning and rebuilding the solution. This worked for me. On some other posts, I have read the replies and most of users solved the problem by following this way.
I removed DLL name and namespace from the path where I was using it. And for some wierd reason it worked.
Make sure that the classes are public classes too. I had this issue when I couldn't find my model classes. Silly mistake but frustrating when unnoticed.
This is mostly cause becauese of using diffrent version of same packages at diffrent projects at same solution. I recommend to update all packages to lastest version at all projects.
Right click to project that has downgrade packages --> manage nuget
packages --> click the updates tab --> check the 'select all packages' checkbox -->
click the update
Do this for all prjects at solution.
I had this problem using Visual Studio 2019 with Resharper. I resolved it by clearing the Resharper cache.
Extensions\Resharper\Options
General Page
"Clear caches" button.
After clicking "Clear caches", I restarted Visual Studio and did a Clean/Rebuild.
VS2019 July 2022: I had to deal with same issue for more than a day.
The comment by JaredPar helped to resolve it :"most likely cause of
this problem is the referenced DLL is itself invalid. Have you tried
loading it in reflector to see if it contains members? –
So If you reference an assembly and IT DOES NOT CONTAIN at least ONE public type(Class, Property ,Enum, .. etc) still it does not show after the using keyword. This behavior makes 100% sense, because what is the point of referencing something which is useless?
However Microsoft could easily have added a Message/Warning in VS to make the life of the developer less Miserable.
Something like "Warning: Reference ABC does not contain any public members"`
We have got a C# Windows application which uses devexpress controls, enterprise library and CC.net for building. We are planning to migrate VS2010 soon.
Have you come across similar situations? Are there any unforeseen issues?
If your code makes use of any of these features listed in column 1, you might need to take a look at this:
http://msdn.microsoft.com/en-us/library/ee855831.aspx
If you are still targeting .NET 3.5 then the move should be very smooth. We recently moved a very large WinForms app across and encountered a couple of minor issues:
Some of our resx files contained serialized generic lists of our own custom types, which caused compile errors. Never got to the bottom of why this was, but we just deleted them from the resx files and set the [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)] attribute on the offending properties
The syntax checking of XML comments is slightly stricter, meaning you could get extra warnings (and with all warnings as errors turned on this broke our build)
We did a similar migration almost a year ago (just after Visual Studio 2010 was released). That was a little bit too early as DevExpress were not quite ready with their .NET 4 version yet. We had to run the web application in "compatibility mode" for a week or so.
There were very few issues. From what I remember (our product is half .NET and half C++):
Some third party controls needed updating
Some internal names crashed with new .NET 4 BCL classes.
C++ project started to use MSBuild so that was some work up upgrade the project files.
I faced this : on XP machine, trying to build a project referencing a COM with multiple objects inside. Specifically, i've encountered this with INetFwMgr - (The type or namespace name 'INetFwMgr' could not be found (are you missing a using directive or an assembly reference?). Its seems that i am not the only one.
EDIT: solution here.