I'm working on a C# 4.0 project in VS2010 and needed to use some older DLLs containing controls that were created in C# 3.5 on VS2008. When I first add the DLLs to the references, I was able to see the namespace via intellisense and create an instance of one of the controls, but when I go to build, it gives me the following error:
The type or namespace name 'BCA' could not be found (are you missing a using directive or an assembly reference?)
And I do have a using directive for that namespace already, which is now underlined in red, showing that VS cannot find it. And now, intellisense won't pick up that namespace at all.
I even tried added the controls to the toolbox (which worked) but then when I drag them to the GUI, it says that it cannot locate the DLL reference, even though it obviously knows where it is.
I even tried changing the target framework to 3.5, but still with the same results.
Any thoughts as to why this could be happening?
Edit - I've notice that in the csc.exe arguments that VS outputs, it does not have any /reference entries for the DLLs I'm trying to use. When I create the same basic project in VS2008, those entries exist. Also, I can successfully reference the DLLs in a DLL project in VS2010... it seems to just be WinForms projects that don't work.
Turns out that it was something to do with VS2010 defaulting to the .NET 4 client profile, as soon as I changed it to the regular profile it built fine. There's a day wasted...
view the target framework.. in my project, was 4.0 client profile, e the reference dll was in 4.0
I tried Build->Clean Solution and then could add the reference.
I used to have similar problem, but the profiles were not the issue, so the problem was that my class library use a special NuGet package that has Dependency... so I install the dependency package in the target project and added the project reference and works!
But I am not sure if there is a better solution for this problem??? for me VS should be smart enough to carry those dlls along with the references. (I already verified that "Copy Local" is set to True)
Related
I am building a .NET WPF application, which was previously targeting .NET 4.6.1.
I have used this tool to convert my previous .csproj into the new Package-Reference csproj style of VS2017.
I have also updated the target framework to .NET 4.7.1.
The issue is that my main project references other projects from my solution, and each of those fails when I declare using namespace;
When I was using the previous csproj style projects, my main project was successfully referencing my other projects inside my solution but it does not anymore.
I have tried disabling ReSharper and I've even checkout the sources to a from scratch Windows installation and I got the same thing.
The weird thing is I got many errors from Intellisense, but everything builds perfectly!
I am running out of idea...
The solution sources are here.
The weird thing is I got many errors from Intellisense, but everything builds perfectly!
well assuming this is the case - intellisense information is stored beside your solution-file in the .vs folder. You can try to close VS, remove the folder and reopen the solution. This usually fixes my problems when dealing Intellisense errors despite successfull builds.
Start with this basic advice: When you have a using statement, you're citing a namespace. In order for that namespace to be resolved, the project in question must have a reference to an assembly or project that contains that namespace. The fact that your DownloadService.cs code module shows that it cannot resolve the Popcorn.Utils namespace tells me that the project that contains DownloadService.cs does not have a reference to the project or assembly that contains Popcorn.Utils.
I've got a project (project A)in vs2010 (c#) that I want to reference another project (.exe) (project B) that I created. Project A is a quick, down & dirty util that I will only use once but I need all the function calls and db calls from project B, so rather than cut, copy, pasting from one to another, I thought I could just reference project B in my references. I am able to point to the .exe and in code i can use it, but when I compile it, it complains about not being able to see it (the infamous "are you missing a using directive or assembly reference?" error).
Does anyone know how I can do this?
Most probably, also it's hard to say, you have .NET Framework version conflict. One of your projects has .NET Framework version which is not compatible with other.
Check in project properties of both of them the version of the framework.
Make them the same
Recompile both of them
and most probably the trouble will gone.
Hope this helps.
Make sure the namespace of classes you want to use from project A is included in the files in your project B in a using directive:
using projA.ExampleNamespace;
I have the same problem. When I first added the reference all worked fine. But some time later after a rebuild there were errors and the classes and namespaces of "project A" were not longer recognized. Removing and re-adding the reference solved the problem immediately (without rebuiling or anything). There were no errors in other code and all DLLs and EXEs were build correctly. Build Order and Build Dependency settings were also correct. Seems to be a strange bug in Visual Studio (I use 2013 Professional).
I also checked how the reference was set in csproj file. The csproj file didn't change at all after removing and re-adding the reference. Neither did the sln file.
Maybe it's some strange caching behavior. But as I used "Rebuild All" which cleans up temporary files imho, this shouldn't happen. Even restarting VS or the PC didn't help.
I'm working on a C# 4.0 project in VS2010 and needed to use some older DLLs containing controls that were created in C# 3.5 on VS2008. When I first add the DLLs to the references, I was able to see the namespace via intellisense and create an instance of one of the controls, but when I go to build, it gives me the following error:
The type or namespace name 'BCA' could not be found (are you missing a using directive or an assembly reference?)
And I do have a using directive for that namespace already, which is now underlined in red, showing that VS cannot find it. And now, intellisense won't pick up that namespace at all.
I even tried added the controls to the toolbox (which worked) but then when I drag them to the GUI, it says that it cannot locate the DLL reference, even though it obviously knows where it is.
I even tried changing the target framework to 3.5, but still with the same results.
Any thoughts as to why this could be happening?
Edit - I've notice that in the csc.exe arguments that VS outputs, it does not have any /reference entries for the DLLs I'm trying to use. When I create the same basic project in VS2008, those entries exist. Also, I can successfully reference the DLLs in a DLL project in VS2010... it seems to just be WinForms projects that don't work.
Turns out that it was something to do with VS2010 defaulting to the .NET 4 client profile, as soon as I changed it to the regular profile it built fine. There's a day wasted...
view the target framework.. in my project, was 4.0 client profile, e the reference dll was in 4.0
I tried Build->Clean Solution and then could add the reference.
I used to have similar problem, but the profiles were not the issue, so the problem was that my class library use a special NuGet package that has Dependency... so I install the dependency package in the target project and added the project reference and works!
But I am not sure if there is a better solution for this problem??? for me VS should be smart enough to carry those dlls along with the references. (I already verified that "Copy Local" is set to True)
My application has a mixture of 3.5 and 4.0-targeted assemblies. I'm working on a new Windows service targeting 4.0 and the project suddenly seems unable to see some of the other assemblies in the solution. Meaning, on build, all references to these certain other assemblies produce the following error:
The type or namespace name '[X]' does not exist in the namespace '[Y]' (are you missing an assembly reference?)
If I delete the project reference and re-add it, the red squigglies go away and Intellisense kicks in again like it's supposed to. All of the other projects in the solution build without issue. But as soon as I try to build this new project, the errors come back.
One of the failing references is to our Core.dll, which targets 3.5. We recently added a CoreEx.dll targeting 4.0, with namespace sharing between the assemblies. The new service can see CoreEx.dll but not Core.dll... i.e., when I begin typing using Core.Utilities... Intellisense picks up on the smaller set of namespaces from CoreEx.dll but does not show any that appear only in Core.dll. I'm pretty sure the solution built successfully after adding this, but it's a notable recent change.
Another failing reference is to our core Data.dll which holds a bunch of datasets and Entity Framework stuff. This one was recently migrated to 4.0. Again, I'm almost positive the solution built after migrating the project, but it's worth mentioning.
The last failing reference is an assembly that uses the namespace one level "up" from the service. E.g., the problematic project is based out of namespace ProductName.Component.ComponentService and it is unable to see the project based out of namespace ProductName.Component. This one was recently created along with the problematic project and also targets 4.0.
As you can see, there doesn't seem to be any rhyme or reason to which assembly references are failing... and the problematic project can successfully reference some of the other assemblies in the solution. I've tried cleaning, re-building, restarting Visual Studio... nothing has fixed it permanently. What could be causing this?
Check the target platform of the new project and make sure it's not targeting .NET 4 Client Profile. If it is, change it to regular .NET 4
I was adding projects to a Solution that utilized .net 4.5. The projects I had added were defaulting to 4.5.1. This rendered 4.5 libraries incompatible with the new projects. I went into the properties of my new projects and had them target 4.5 instead of the default 4.5.1. After I had done that, my solution was able to build.
Are the dependencies set correctly in the solution? I have seen more than one occasion where Project A depends on Project B, but because the dependency between the two was not set the build fails sporadically.
The underlying cause in this case is that the build is order is not deterministic and success/failure depends on things like which projects build (based on what changed) and which builds first (when more than one builds).
It worked for me when I changed the target framework to 4.0..But that was not the solution we wanted..We Wanted to use VS 2010 Premium for our project but the intention was NOT to use .net 4.0...The main class library project(.net 2.0) was referencing the dll "system.web.abstractions.dll"...I added the reference to this dll in other projects(.net 2.0) which references the main class library...the solution compiled without any problems...so it could be the case with your visual studio solution...
But everything works fine if we use VS 2008 professional..we need no workaround & everything works like magic...
Please also note it can happen if you change the namespace but you did not changed the Assembly name in the project properties.
This problem happened to me once I solved it by deleting all the using statements on top and manually writing them again.
I had a similar issue, an assembly reference fail (“Are you missing a using directive or an assembly reference?”) and the VS intellisense gave me the opportunity to add the using but in the solution the reference had the yellow icon and the build was failing.
I solved this looking at the project property Target Framework and changing the .net version to the reference solution version and this solved all problems.
Note: The .net versions should be compatible between projects.
When I add a reference to my dll in Visual Studio project, I am able to use it, but when I compile my code or try to run it, I get an are you missing a using directive or an assembly reference?_ Error. I am able to confirm that I have the right using statement for my namespace and I am able to confirm that the dll is correctly loaded.
Anyone have any idea what I may not have right in this?
Go to project settings and make sure that you are not compiling the project for a .net version that includes the text "client profile".
I had just had an issue precisely like this, even if this is an old question thought I would add my 2c on what fixed it as none of the other answers helped:
For whatever reason, when I built the solution top to bottom a certain dll was not getting updated and output that held changed code. So while my solution had no visible errors, when you attempted to build, it was still referencing the old dll and started complaining.
It was simply a case of directly re-building the offending project and after that it picked up the latest dll and built happily.
This seemed to be a freak accident as no configuration had changed between when it worked / when it didn't.
Sometimes, JUST REBUILD THE SOLUTION.
The location of the DLL is important.
If you add a reference on your local machine to a DLL that is outside of your Visual Studio solution, it isn't necessarily copied into your solution files (depends on the type of solution/project).
If this is your problem, then you need to either put the DLL in the same path on the other machine, or copy it into your solution so it gets deployed along with the solution files, and change the reference.
You can also handle this with build instructions, but that might be beyond your aspirations at the moment.
Most likely your dll is referencing another dll that the client project is not referencing and your dll code is exposing a type or an interface from the 3rd dll to the client code.
If you post the exaCt message, we'll be able to help better.
Are you using .net 4.0?
If yes, this dll is probably not compatible with .net 4.0
In my case, the main project (WinForm) was configured Framework Target: FW 4.0 "client profile". I change to FW 4.0 and work perfect!!.
At first time i was looking in the referenced projects and they were ok, but de main project doesn't. I hope this help. Thank you.
In my case this compilation error has gone after adding the reference to Microsoft BCL Build Components via "Manage NuGet packages" context menu on problem project.
Before: I had project Main (console application) referencing project A (class library).
Project A had dependency on Microsoft BCL Build Components.
After: I started refactoring where I picked out several classes to the separate project New. It also depended on A. But the compilation error occurred on project New as if there was no reference New -> A (although Visual Studio didn't highlight allegedly not found interfaces and classes listed in the error list of compilation).
So I checked project A's dependencies and found there Microsoft BCL Build Components.
After adding it to New's dependencies everything worked fine.
The most interesting thing is that Main did not contain this dependency and it didn't need it.
Hope this helps.
You just Have to check your namespace of that class file again...it will work