In a legacy project I am working on, there is a using directive:
using System.Web.Hosting
I supposed, that the nuget package name should be System.Web and tried to install it via Nuget.
But there's no such package.
Question: where can I get this package and how?
System.Web is not a nuget-package, it's a framework reference and System.Web.Hosting is one of the namespaces located in System.Web
Depending on your project-type, whether it's the old or new format, you have to do the following
For old format:
Locate the project and collapse it
Right click on "References" and press on "Add reference"
In the window that pops choose the menu on the left named "Assemblies" and then search for "System.Web"
For new format:
Right click on the project and press on "Edit"
Find an existing <ItemGroup> or add a new one
Add this line <Reference Include="System.Web" />
I did not know that System.Web is not available for .netstandard projects. And my project is a .netstandard project (migrating from .net framework).
This is the reason why the System.Web package is not available. I think it would be far more better, if unavailable packages would be displayed, but with message, that they are not availble for a particular reason.
Otherwise users spend much time to finding out the reason of such issue.
Related
First of all I don't know if what I'm doing is fundamentally the wrong idea, so the answer could be to just not do this, but here goes..
I have a package that I'm creating from a .nuspec file, in its "files" section it contains references to both .net standard and .net framework DLLs. It also has dependencies on both .netstandard20 and .netframework47.
The reason behind this being that the legacy libraries are written in framework, and the new ones are being written in standard.
We have a consuming project (actually, several), written in .netframework 4.7 that needs to address both sets of DLLs. I have changed the project to use PackageReference rather than packages.config, and
Visual Studio shows that the package is being referenced (rather than the individual namespaces) in the References section. When I build, the .netframework DLLs get copied into the bin folder, but not the .netstandard DLL.
I've created a scratch project to isolate the issue, and I'm seeing the same there as well. The project basically just refuses to acknowledge the standard one. If I add a using statement into a class with a type from the .netstandard DLL it just puts a red squiggly under it and tells me it doesn't exist in the namespace.
It's been suggested that I break the .netstandard DLLs out into their own NuGet package, is that the answer or am I missing something?
Here's some examples..
The .nuspec file:
<?xml version="1.0" encoding="utf-8"?>
<package >
<metadata minClientVersion="2.5">
<!-- other tags removed for brevity -->
<dependencies>
<group targetFramework=".NETStandard2.0"></group>
<group targetFramework=".NETFramework4.7">
<dependency id="NLog" version="3.1.0.0" />
</group>
</dependencies>
</metadata>
<files>
<file src="..\Src\MyProj1\bin\Release\netstandard2.0\NetStandardClass.dll" target="lib\netstandard2.0" />
<file src="..\Src\MyProj2\bin\Release\NetFrameworkClass1.dll" target="lib\net47" />
<file src="..\Src\MyProj3\bin\Release\NetFrameworkClass2.dll" target="lib\net47" />
</files>
</package>
The package is referenced as a package, not the individual types within it:
If I try to manually add a using statement referencing the NetStandardClass's namespace it's marked as an error
The package itself contains all 3 DLLs as expected:
Yet when I build the project and inspect the bin folder, the NetStandardClass DLL is not there:
It's been suggested that I break the .netstandard DLLs out into their own NuGet package, is that the answer or am I missing something?
Basically, yes, splitting the package is the answer. Another possibility is to move the netstandard assemblies into the net47 folder, or maybe the net47 assemblies into the netstandard2.0 folder, but either way has potential for problems. Although solution is to recompile all your assemblies so they all use the same target framework, but that also has its own issues.
If you had read the NuGet docs and came to the conclusion that what you're attempting should work, please point me to which docs lead you to believe that, so I can update the docs and try to remove the confusion.
The first thing to understand about why NuGet supports a package having multiple target framework folders is because a package might want to use new framework features where possible, but have support for users of the package using older frameworks. Therefore, the package author needs multiple versions of their assembly, depending on which one is compatible with their users project. So, the point is that NuGet needs to select assets from the package depending on which target framework moniker (TFM) the project uses. The way NuGet actually does asset selection is as follows:
NuGet looks are which TFM folders exist in the package, to get a list of TFMs that the package supports. Generially it looks for lib/<tfm>/ and ref/<tfm> folders, but contentFiles/<tfm> and build/<tfm> files might be relevant as well. Notice it doesn't look at any filenames. Which assemblies exist under lib/net47/*.dll or lib/netstanard2.0/*.dll are not yet considered.
Once it has this list of package TFMs, it looks at the project TFM, and it selects the "best" TFM. For SDK style projects that multi-target, it does this once per project TFM. "Best" TFM means same "family" (net* projects always choose net* assets, if available. only when no net* assemblies exist does netstandard compatible .NET Framework TFMs look for netstandard* assets).
Once a package TFM is selected for the project's TFM, then NuGet selects all the files like lib/<tfm>/*.dll, ref/<tfm>/*.dll, contentFiles/<tfm>/<lang>/*, build/<tfm>/<package_id>.<props|targets>, and so on.
So, you can see that if your package contains lib/net47/assembly1.dll and lib/netstandard2.0/assembly2.dll, NuGet will only ever select one of the two assemblies, never both, depending on if net47 or netstandard2.0 is more compatible with the project.
Although it might seem desirable for you if NuGet did TFM selection per TFM, rather than selecting TFM first and then selecting only the assemblies that exist in that folder, consider when a package adds an additional helper utility to "polyfill" old TFMs with features that the package uses in newer TFMs. This helper utility is not needed for newer TFMs, so it would be undesirable for NuGet to select it.
The NuGet team suggests creating one package per assembly, in which case this problem never would have occured, because NuGet would have done asset selection per package, and assuming each package was authored correctly, everything just selects selected correctly. If you insist on bundling all the assemblies in a single package, from my description above I hope you see you need to put all the assemblies in a single TFM folder, but since different assemblies were compiled against different TFMs, there's potential for problems, particularly if some developers are using older versions of Visual Studio that might not support .NET Standard. I very strongly recommend at the very least creating one package per TFM, or recompiling all the assemblies to use the same TFM.
Previously, we used the project.json to setup our projects dependencies. The Asp.net Core team moved away from that and went back to using .csproj. However, when trying to type in the name of a package, it no longer auto-completes like it used to.
For instance, typing in the following line would show intellisense when I typed the . after Microsoft, providing me with the packages within that namespace.
<PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="1.1.2" PrivateAssets="All" />
How do I get this functionality back?
It's still there in a Editor Extension called "Project File Tools" which is a Microsoft Extension and I am pretty certain this should be installed by default, but on VS 15.3 Preview it didn't seem to be working (was installed, but I didn't had any other extensions there). Somewhere in between disabling/restarting/enabling it and/or installing the Web Essentials it started working again.
As for Ctrl+. doing a reverse package search, it's there too but disabled by default:
Go to Tools > Options > Text Editor > C# > Advanced (or hit Ctrl+Q and type "C# Adv" + Enter) and check "Suggest usings for types in NuGet packages".
If you already have a highlighted error before setting the changes you got to remove the piece of code and add it again before it gets recognized (read: it only applies for red-squiggles that happen after the change).
This will probably depend on which IDE you are using.
If you're using Visual Studio then you'd right click on dependencies or csproj then click "Manage Nuget Packages".
This will open a view where you can search for packages and install them.
If you're using Visual Studio Code, there are couple of plugins that'll help you search and add packages you're looking for.
https://marketplace.visualstudio.com/items?itemName=jmrog.vscode-nuget-package-manager
Lets you search package and add specific version.
I am getting the following issue while compiling my project. It is a MVC 5 application. Here is the error:
Severity Code Description Project File Line Suppression State
Error This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them. For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is ..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props. WikidoctorAdmin E:\My Projects\Wiki-Doctor\Wiki-Doctor.com\Wiki-Doctor.com\WikidoctorAdmin\WikidoctorAdmin.csproj 2107
Please help me how to solve this error.
I had the same issue and solve it by opening the project in a text editor and deleting the following section:
<Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
<PropertyGroup>
<ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them. For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
</PropertyGroup>
<Error Condition="!Exists('..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props'))" />
<Error Condition="!Exists('..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.0\build\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.0\build\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props'))" />
</Target>
I didn't need Nuget for this project.
Hope this helps.
You can fix this one of two ways:
Under Tools/Nuget Package Manager:
Menu screen capture
1) Choose the first option (Package manager Console).
Package manager console window will appear (Usually toward the bottom of the screen)
You should see a button that says "Restore Missing packages"...Click it.
This method will work for this project only...and you will have you redo this for each project with missing packages
2) Choose Package Manager settings
Make sure the check box that says "Allow Nuget to download missing
packages" is checked
Re-build your solution
Nuget will automatically download missing packages from now on. This is easier, but might not always be what you want.
The name of the project is longer than 248 characters. You need to rename the path under 248 characters, then open solution and rebuild and the nuget will be updated.
that worked for me having similar error -
go to your complaining project references - find references with yellow marks
open solution nuget package manager and 'reinstall' nuget packages which have those yellow marked dlls.
easy way to reinstall one by one - select nuget in the right, in the left upper portion there would be checked projects.
in the left lower portion - select one version down, install, select one version up (your needed version), install - repeat for all questioned nugets
I've got the same problem, and I solved this way:
- erase every obj and bin folders under the solution projects,
- using the NuGet Package manager to restore and update all packages.
Hope it helps.
When I creating webtests I want to add "Web Test Plug-in" I get message box with information that one of my nuget library is missing.
Whole my solution is compilable and this "missing" library exists as entry in csproj and config files. After compilation of test project this library is inside "bIn" folder. I check under dotPeek version, publicToken etc is correct.
My question is where webtest project look for this library?
If the webtests is missing a dependency:
Right click solution > manage nuget packages for solution > click manage on the package in question, then select your webtests project > ok.
If the webtests has a broken link to a dll :
Look at the references, and see if there are any yellow triangles, and where they point to. If that is the case, delete that reference and re-attach.
So im downloading a project at home from work over team foundation server. I download the project and it won't compile because of the error. Warning 2 The referenced component 'EntityFramework' could not be found. Could anyone offer guidance in how I can get entity framework to work. I installed nuget package.
Thankyou
I suggest you to check:
1) "Allow NuGet to download missing packages during build" ticked
Tool --> Options... --> Package Manager --> General
2) "Project selected" ticked
Solution Explorer --> right-click on the solution/project --> Manage NuPackages
3) Rebuild Solution
EDIT
For completeness I would like to add that if you are working with a CI system (e.g. Jenkins) or you are using MSBuild on the command line, you need to select Enable NuGet Package Restore to make it work:
Enable NuGet Package Restore http://docs.nuget.org/docs/Workflows/images/enable-package-restore.png
I had the same problem. I solved it like this:
Choose References > Right-click > Add Reference ...
Choose Browse tab
Find your Project Folder > packages > EntityFramework.4.1.10331.0 > lib
Choose EntityFramework.dll
Click OK
This happened to me, after I moved projects to a subfolder.
Then, the relative paths to the packages folder were not correct anymore.
Got errors like that:
This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them. For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is ..\packages\NETStandard.Library.2.0.1\build\netstandard2.0\NETStandard.Library.targets. PROJECTNAME D:\VSTS\TEAMPROJECT\src\PROJECTFOLDER\PROJECTNAME.csproj
Fixed it by editing the *.csproj file and corrected the relative paths, in my case from ..\packages to ..\..\packages
Also make sure to check the paths under
<Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
There are good ways suggested by the developers, you may also try this solution to solve your problem.
In your case your project has a reference to the EntityFramework library, but library it self is not available to you project. You may try either the following:
If you have NuGet package manager:
Click on Project-> Manage NuGet Packages. It will open following window.
Find the EntityFramework and click Install.
- Alternatively, Download the EntityFramework library to your computer, then
Right-Click the Prject-> Add References...-> Browse-> Locate your
EntityFramework library-> Click OK
- Optionally you may use package manager to install library reference, check this link package-manager-console (Note: This might require NuGet Package manager)
I solved this issue by adding Entity Framework reference (Add ref) under C:\ Prog Files\Entity...\Binaries\Entity Framework.dll into my project. Hope this helps!
An old thread, but for anyone that this may help..
What worked for me was to go to the 'Packages' folder in the root of my solution and delete the EntityFramework.6.4.4 folder.
Then, go to Manage Nuget Packages menu option, and this banner pops up:
After pressing Restore the missing reference was restored.