I have a visual studio solution.
I have many projects in the solution.
There is one main project which acts as the start up and uses other projects.
There is one project say "ProjectX". Its reference is added to main project.
The ProjectX references another .NET dll (say abc.dll) that isn't part of the solution.
Now this abc.dll should be copied to bin/debug folder of main project, but it isn't getting copied there. Why is it not getting copied, any known reasons ?
I found that if ProjectX referenced the abc.dll but didn't directly use any of the types DEFINED in abc.dll, then abc.dll would NOT be copied to the main output folder. (It would be copied to the ProjectX output folder, to make it extra-confusing.)
So, if you're not explicitly using any of the types from abc.dll anywhere in ProjectX, then put a dummy declaration somewhere in one of the files in ProjectX.
AbcDll.AnyClass dummy006; // this will be enough to cause the DLL to be copied
You don't need to do this for every class -- just once will be enough to make the DLL copy and everything work as expected.
Addendum: Note that this may work for debug mode, but NOT for release. See #nvirth's answer for details.
Just a sidenote to Overlord Zurg's answer.
I've added the dummy reference this way, and it worked in Debug mode:
public class DummyClass
{
private static void Dummy()
{
var dummy = typeof(AbcDll.AnyClass);
}
}
But in Release mode, the dependent dll still did not get copied.
This worked however:
public class DummyClass
{
private static void Dummy()
{
Action<Type> noop = _ => {};
var dummy = typeof(AbcDll.AnyClass);
noop(dummy);
}
}
This infomation actually costed me hours to figure out, so I thought I share it.
Yes, you'll need to set Copy Local to true. However, I'm pretty sure you'll also need to reference that assembly from the main project and set Copy Local to true as well - it doesn't just get copied from a dependent assembly.
You can get to the Copy Local property by clicking on the assembly under References and pressing F4.
It looks slick when you make it an assembly attribute
[AttributeUsage(AttributeTargets.Assembly)]
public class ForceAssemblyReference: Attribute
{
public ForceAssemblyReference(Type forcedType)
{
//not sure if these two lines are required since
//the type is passed to constructor as parameter,
//thus effectively being used
Action<Type> noop = _ => { };
noop(forcedType);
}
}
The usage will be:
[assembly: ForceAssemblyReference(typeof(AbcDll.AnyClass))]
Ran into this same issue. Background info: before building, I had added a new Project X to the solution. Project Y depended on Project X and Project A, B, C depended on Project Y.
Build errors were that Project A, B, C, Y, and X dlls could not be found.
Root cause was that newly created Project X targeted .NET 4.5 while the rest of the solution projects targeted .NET 4.5.1. Project X didn't build causing the rest of the Projects to not build either.
Make sure any newly added Projects target the same .NET version as the rest of the solution.
Not sure if this helps but for me, many times I reference a DLL (which automatically adds it to the bin folder of course). However that DLL might need additional DLLs (depending on what functions I'm using). I do NOT want to reference those in my Project because they just simply need to end up in the same folder as the DLL I am actually using.
I accomplish this in Visual Studio by "Adding an existing file". You should be able to add it anywhere except the Add_data folder. personally I just add it to the root.
Then change the properties of that file to ...
Build Action = None (having this set to something like Content actually copies the "root" version to the root, plus a copy in the Bin).
Copy to output folder = Copy if Newer (Basically puts it in the BIN folder only if it is missing, but doesn't do it after that)
When I publish.. my added DLL's only exists in the BIN folder and nowhere else in the Publish location (which is what I want).
You could also check to make sure the DLLs you're looking for aren't included in the GAC. I believe Visual Studio is being smart about not copying those files if it already exists in the GAC on the build machine.
I recently ran in this situation where I'd been testing an SSIS package that needed assemblies to exist in the GAC. I'd since forgotten that and was wondering why those DLLs weren't coming out during a build.
To check what's in the GAC (from a Visual Studio Developer Command Prompt):
gacutil -l
Or output to a file to make it easier to read:
gacutil -l > output.txt
notepad.exe output.txt
To remove an assembly:
gacutil -u MyProjectAssemblyName
I should also note, that once I removed the files from the GAC they were correctly output in the \bin directory after a build (Even for assemblies that were not directly referenced in the root project). This was on Visual Studio 2013 Update 5.
If you right Click the referenced assembly, you will see a property called Copy Local. If Copy Local is set to true, then the assembly should be included in the bin. However, there seams to be a problem with Visual studio, that sometimes it does not include the referenced dll in the bin folder... this is the workaround that worked for me:
In my case, it was the stupidest thing, caused by a default behavior of TFS/VS that I disagree with.
Since adding the dll as a reference to the main project did not work, I decided to add it as an "Existing Item", with Copy Local = Always. Even then the file was not there.
Turns out that, even though the file is present on the VS Solution and everything compiled both locally and on the server, VS/TFS did not add actually add the file to source control. It was not included on the "Pending Changes" at all. I had to manually go to the Source Control Explorer and explicitly click on the "Add items to folder" icon.
Stupid because I've been developing for 15 years in VS. I've run into this before, I just did not remember and somehow I missed it because everything still compiled because of the file being a regular reference, but the file that was added as Existing Item was not being copied because it did not exist on the source control server.
I hope this saves someone some time, since I lost 2 days of my life to this.
Issue:
Encountered with a similar issue for a NuGet package DLL (Newtonsoft.json.dll) where the build output doesn't include the referenced DLL. But the compilation goes thru fine.
Fix:
Go through your projects in a text editor and look for references with "Private" tags in them. Like True or False. “Private” is a synonym for “Copy Local.” Somewhere in the actions, MSBuild is taking to locate dependencies, it’s finding your dependency somewhere else and deciding not to copy it.
So, go through each .csproj/.vbproj file and remove the tags manually. Rebuild, and everything works in both Visual Studio and MSBuild. Once you’ve got that working, you can go back in and update the to where you think they need to be.
Reference:
https://www.paraesthesia.com/archive/2008/02/13/what-to-do-if-copy-local-works-in-vs-but.aspx/
Make sure that the dependent DLL used by you does not have target .NET Framework higher than the target .NET framework of your project's Application.
You can check this by selecting your project, then press ALT+ENTER, then select Application from left side and then select Target Framework of your project.
Suppose,
dependent DLL Target Framework = 4.0 and
Application DLL Target Framework = 3.5 then change this to 4.0
Thank you!
This is a slight tweak on nvirth's example
internal class DummyClass
{
private static void Dummy()
{
Noop(typeof(AbcDll.AnyClass));
}
private static void Noop(Type _) { }
}
I would do add it to Postbuild events to copy necessary libraries to the output directories. Something like XCopy pathtolibraries targetdirectory
You can find them on project properties -> Build Events.
TLDR; Visual Studio 2019 may simply need a restart.
I encountered this situation using projects based on Microsoft.NET.Sdk project.
<Project Sdk="Microsoft.NET.Sdk">
Specifically:
Project1: targets .netstandard2.1
references Microsoft.Extensions.Logging.Console via Nuget
Project2: targets .netstandard2.1
references Project1 via a Project reference
Project2Tests: targets .netcoreapp3.1
references Project2 via a Project reference
At test execution, I received the error messaging indicating that Microsoft.Extensions.Logging.Console could not be found, and it was indeed not in the output directory.
I decided to work around the issue by adding Microsoft.Extensions.Logging.Console to Project2, only to discover that Visual Studio's Nuget Manager did not list Microsoft.Extensions.Logging.Console as installed in Project1, despite it's presence in the Project1.csproj file.
A simple shut down and restart of Visual Studio resolved the problem without the need to add an extra reference. Perhaps this will save someone 45 minutes of lost productivity :-)
You may set both the main project and ProjectX's build output path to the same folder, then you can get all the dlls you need in that folder.
NO NEED FOR DUMMY IN CODE
Just :
add a Reference to the Executeable Project
or/and ensure that the reference in the executeable project has "Copy Local" set to TRUE (which was my "fault") is seems that this "overwrote" the setting in the base referenced library-project...
Other than the common ones above, I had a multi-project solution to publish. Apparently some files target different frameworks.
So my solution: Properties > Specific Version (False)
Add the DLL as an existing item to one of the projects and it should be sorted
VS2019 V16.6.3
For me the problem was somehow the main .proj file ended up with an entry like this for the project whose DLL wasn't getting copied to the parent project bin folder:
<ProjectReference Include="Project B.csproj">
<Project>{blah blah}</Project>
<Name>Project B</Name>
<Private>True</Private>
</ProjectReference>
I manually deleted the line <Private>True</Private> and the DLL was then copied to the main project bin folder on every build of the main project.
If you go to the reference of the problem project in the references folder of the main project, click it and view properties there is a "Copy Local" setting. The private tag equates to this setting, but for me for some reason changing copy local had no effect on the private tag in the .proj file.
Annoyingly I didn't change the copy local value for the reference, no idea how it got set that way and another day wasted tracking down a stupid problem with VS.
Thanks to all the other answers that helped zone me in on the cause.
HTH
I had a similar issue in which a DLL I had included in the project as content and 'Copy always' set, wasn't being copied to the bin folder. I solved this by adding a dependentAssembly reference to the DLL in the app.config.
Please any one explain this. This Question helps to understand common things
Question:
What is the difference between when you 'add DLL reference from one project to another project via Browse Option and Add DLL reference from Solution project to another project and copy-paste from one project to another project'?
I have found an answer on google
Answer:
Adding a project reference adds a local project's DLL to the project that references it, and every time the solution compiles, the updated DLL for that project gets copied to the other project. So when you go through the build process, if you have 5 projects, each one rebuilds its DLL, and copies that DLL to its references.
But:
I don't know what the process is and the difference when we copy-paste from one project to another project?
When you do copy paste from One project to another, the dependent project add its reference of the file that you have paste in the project solution directory
When you do copy paste the dll of one project to the other project's directory and then Add its reference by browsing to that directory where you have pasted your dll. Then VS only add its reference and copy that dll to its bin folder and show you (allows you) all the method and properties that it contains.
If you do any change in your source project solution like adding or modifying methods then the updated dll of that project is not available in your dependent project solution.
So VS still points to the old dll file just because of the reference you added. So whenever you made any change in your source project solution, you have to add the reference of the updated dll to your dependent solution every time.
In Second Case: When you add reference of your source project into your dependent project solution, VS always take the most recent updated dll from your source project into your dependent project. So in this way you don't need to add reference every time you compile the code or debug.
When you just reference a DLL by browsing to it, VS would copy it to the output directory of the dependent project.
Suppose afterwards that DLL is updated - there is no guaranty that VS would retake that updated DLL, and copy it again to the output directory of the dependent project - which mean, that even after you fixed some bugs in the other project, those bug would persist in the dependent project (because it is still using the previous version of that DLL).
When you add reference to other project in the solution, VS would always take the most recent and updated DLL outputted from that project.
I have been working on an ASP.NET project for months now without issue. Recently my computer crashed mid compile and now when I load and run the project I get 'Could not load file or assembly 'Ionic.Zip' or one of its dependencies.'
Thinking it was an issue with that particular DLL, I removed it as a test only to have the project say it could not load another referenced DLL, etc etc, until I had no references left...
Any ideas?
If nothing in the code has changed. "Build->Rebuild Solution" should do the trick (implicitly cleans and builds).
If this does not work, do "Build->Clean solution" and go delete all generated build folders (default bin and obj folders). And then try build and run.
And if it still does not work, the code has changed and dependencies are really missing.
Using NuGet and packages are missing perhaps?
I tried everything but NuGet, I didn't use it to get any of the references before.
In the end I had to check in all my changes to TFS, delete the project from my workspace and computer, and then reload it from TFS. Seems to have worked. Something must have been damaged in the project file.
I've got a project on a computer with installed devexpress line for win forms. In VS2010 I add references to some of devexpress .dll(s) and mark those references as 'Copy Local' and build project. Than I send a folder with a project to another user whose machine has not installed devexpress on it. When he opens the solution all devexpress references are shown as broken and the assembly won't compile.
The output is as the following:
C:\Windows\Microsoft.NET\Framework\v4.0.30319\Microsoft.Common.targets(1578,5):
warning MSB3245: Could not resolve this reference. Could not locate the assembly
"DevExpress.Data.v13.1, Version=13.1.8.0, Culture=neutral, PublicKeyToken=b88d1754d700e49a".
Check to make sure the assembly exists on disk.
If this reference is required by your code, you may get compilation errors.
How to add references to the assembly correctly so as I can open it on a machine with no such .dll(s) installed?
"Copy Local" option is copying files to the published directories after building process.
You can include these dlls in the separated solution folder, reference VisualStudio to them and commit this folder with solution to svn or tfs.
In order to do that you need to add the references via Add Reference... / Browse. In the csproj file for your project you should have something like:
<Reference Include="Name.Of.Assembly">
<HintPath>Relative\Path\ToAssemblyFile.dll</HintPath>
</Reference>
BUT VisualStudio tries to be smart and adds the Reference to the installed assemblies, even if you choose Browse... to add them.
You can either:
Not install the DevExpress package and only copy the DLLs to your development machine
Manually edit the .csproj file
Either way, you need to keep the DLLs somewhere. I usually put them under source control.
To achieve this, you should add the DevExpress (or other third-party) assemblies to a folder under your solution root directory, then reference the assemblies in this folder rather than referencing the DevExpress install directory.
You should also add the third-party assemblies to source control, so they're available to all developers.
If the other developer hasn't installed a DevExpress license, it will still build, but will display a nag screen at runtime.
during development of our application we use a branching structure and while we are developing another team is using earlier builds of our software to create content with it.
To facilitate easy swapping between builds and teams I was hoping to use empty Hintpaths in the content projects' csproj files so that they can use our GAC installed assemblies to build against and in the meantime add a reference path to the projects for our use during development and test cycles where we don't want any assemblies installed in the GAC.
However, it seems reference paths are not stored in the csproj file and thus don't get sourcecontrolled. Since there will be extensive branching it would be less than ideal to have to set all reference paths again when a developer pulls another branch from sourcecontrol.
I've been searching for a bit now and can't seem to find ways to do this. Anybody know of a way to force the reference path in and out of sourcecontrol?
We're talking Visual Studio 2008 and TFS 2008 here.
Cheers,
Anton.
Ok, I seem to be a little clearer in the head after a good night's sleep, took the logical step, namely investigate where exactly the information was stored and how. It turned out the information was stored in the .user file for the project in the project's folder and as it turens out this file contains mbsuild xml.
I then did what I wanted as follows:
Create the Reference path as I required it to facilitate both scenarios without any work.
Browse to the Project's .user file
Copy the PropertyGroup containing the ReferencePath
Paste the PropertyGroup in all the necessary Projects' .csproj xml.
Reload and build.
Done.
The references are stored in the *.csproj file. The nodes are ItemGroup/Reference...
Thomas
This is pretty simple--we do this in our shop.
First, in the Workspace (using Windows Explorer, browse to the Solution folder), create a folder. We name it "Referenced Assemblies". In here, drop all your DLLs.
Now, in the Solution, add a new folder to match the one created in Windows Explorer. Into that folder, add all the DLLs you just dropped in.
Finally, in each project, set up your references to use the DLLs that were added to the solution.
Now your project references DLLs that are part of the solution, so that when the build runs, it will grab the DLL from Source Control to generate the build.
Also, I'd recommend not using the GAC at all if you can avoid it. In my experience, reference behavior is strange. It seems references go first to the GAC, then to the DLL in the local folder, meaning that if the DLL is updated, the one in the GAC is used instead of the DLL in the local folder (which is likely the updated one).