I have tried all the suggestions below but still no joy.
I'm now trying a console application, and let me explain exactly what I'm doing.
I create a new console project in VS 2010
I add a number of references (dll's) some that aren't mine such as Castle.Winsor and N2 CMS dlls
in the console app I can add using statements indicating I am using name spaces within the referenced DLLs
I start writing code.
As soon as I compile all the code that uses the referenced DLLs immediately complains with "The type or namespace name '' could not be found (are you missing a using directive or an assembly reference?)"
I have tried setting the dlls to copy to local always, I have copied the DLL into the same directory, I have tried added reference by project and adding a reference to the DLL's themselves
I don't get this problem with a web application project or a ASP.net project they always work fine, only something that is compiled to an EXE like a console app or windows service.
there must be something I'm missing or I would have got this working by now.
Change the project Target to a non Client Profile target. Right click the Project and select Properties, you should see a list of Framework versions. As you are using VS2010, the Console project you've created by default targets .NET Framework 4.0 Client Profile, change that to .NET Framework 4.0.
Check if Copy Local is set to true for the referenced assembly.
First, as to your question, its hard to know exactly what you're doing wrong, but from the fact that you're using an underscore in an assembly name (and probably in namespaces and type names), it suggests you're rather new to the .NET world.
This suggests that you're adding references to other projects in your solution by browsing to the compiled assembly, rather than by adding a Project Reference. When adding a reference, you must select the Project tab rather than browsing for the assembly.
Even if you don't believe this is the issue, remove all references and re-add project references to make absolutely sure. Assumption, asses etc.
Once you've done that, I'd strongly suggest remove all the underscores from your types, namespaces and assemblies. You might want to go read the framework design guidelines, too.
Open your .Proj(Windows service project file) file in notepad and check whether your assembly location(data_object) is the same which you are pointing.
When you open .Proj file in notepad you can check for,
Project reference,
<ProjectReference Include="C:\StackOverflow\StackOverflow.csproj">
And if you giving dll or exe refrence then
<Reference Include="StackOverflow, Version=1.0.0.0, Culture=neutral, processorArchitecture=x86">
<SpecificVersion>False</SpecificVersion>
<ExecutableExtension>.exe</ExecutableExtension>
<HintPath>C:\StackOverflow\bin\Debug\StackOverflow.exe</HintPath>
</Reference>
I suggest you to give exact location including drive name like above example.
Other option you may try,
1. Clean and rebuild
2. Add Project reference if you already tried dll reference
3. Check whether the folder (referred assembly location) is Read Only then remove it.
In VS 2019, I had two projects, one C++ and other one C# Console in one solution file. When tried to add a dll reference through "Add reference", I was not able to see Browse button in "Reference Manager" window, to select dll file.
But when I created only C# Console app inside solution then I could add dll reference.
Related
Well, I'm not familiar with C#. Here's my story:
In the VS2010 solution, there are 2 projects: Entrance, Core and Plugin. Entrance may be compiled into an exe, while the others may produce dlls. Core is added to Entrance's and Plugin's reference. Plugin is set to be compiled to plugin folder. So after compiling, the output directory contains:
entrance.exe
core.dll
plugin\core.dll
plugin\plugin.dll
How can I remove the duplicate core.dll under plugin? Thanks.
In the Solution view of the plugin project, right-click on the core.dll reference and select Properties. Set Copy Local to false to prohibit copying of the assembly to the output directory. Note this will only work properly at runtime if the referenced assembly can be found by the application. In your case it's fine since core.dll is also referenced my the application but that might not always be so.
I'm using a mysql .NET Connector library (Mysql.Data) in my project. As far as I understand it, I only need to use the mysqldata.dll which is in the assemblies folder after the connector is installed. I'm going to be using the program on a computer that has .NET 2.0 but doesn't have the connector.
How do I add the .dll file to a project such that the dll is used internally - I hope that makes sense. If the program calls out to .NET to find it, (as it does) - the whole thing fails and errors out.
In Solution Explorer, under your project, expand References, select the MySql.Data assembly, view the Properties for the assembly, and change Copy Local to True. Now when you compile the project, MySql.Data.dll will be output to the bin directory.
(You will not embed one assembly into another. Instead, you deploy the MySql.Data.dll along with everything else in your build output which is required. This is simply known as adding a reference ... I don't think you really wanted to embed it.)
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.
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
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)