Cannot find command 'dotnet ef'?

问题

I am using .NET core 2.0 on Arch VScode and trying to get EF tools to work but I keep getting that error 'cannot find command dotnet ef'. I've just about looked everywhere and none of the suggestions worked. So if you can please help that would be much appreciated.

The result of running 'dotnet ef'

[wasiim@wasiim-PC WebApiServerApp]$ dotnet ef --help
Cannot find command 'dotnet ef', please run the following command to install

dotnet tool install --global dotnet-ef
[wasiim@wasiim-PC WebApiServerApp]$ dotnet tool list -g
Package Id            Version      Commands        
---------------------------------------------------
dotnet-dev-certs      2.2.0        dotnet-dev-certs
dotnet-ef             2.2.3        dotnet-ef       
[wasiim@wasiim-PC WebApiServerApp]$ 

this is the dotnet --info result, if it's of help

[wasiim@wasiim-PC WebApiServerApp]$ dotnet --info
.NET Core SDK (reflecting any global.json):
 Version:   2.2.105
 Commit:    7cecb35b92

Runtime Environment:
 OS Name:     arch
 OS Version:  
 OS Platform: Linux
 RID:         arch-x64
 Base Path:   /opt/dotnet/sdk/2.2.105/

Host (useful for support):
  Version: 2.2.3
  Commit:  6b8ad509b6

.NET Core SDKs installed:
  2.2.105 [/opt/dotnet/sdk]

.NET Core runtimes installed:
  Microsoft.NETCore.App 2.2.3 [/opt/dotnet/shared/Microsoft.NETCore.App]

To install additional .NET Core runtimes or SDKs:
  https://aka.ms/dotnet-download

This is my .csproj file

<Project Sdk="Microsoft.NET.Sdk.Web">

  <PropertyGroup>
    <TargetFramework>netcoreapp2.2</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <Folder Include="wwwroot\" />
  </ItemGroup>

  <ItemGroup>
    <PackageReference Include="Lucene.Net.Analysis.Common" Version="4.8.0-beta00005" />
    <PackageReference Include="Lucene.Net.QueryParser" Version="4.8.0-beta00005" />
    <PackageReference Include="Microsoft.AspNetCore.App" Version="2.2.5" />
   <PackageReference Include="Lucene.Net" Version="4.8.0-beta00005" />
    <PackageGroup Include="Microsoft.EntityFrameworkCore.SqlServer" Version="1.1.0" />
    <PackageReference Include="Microsoft.AspNetCore.Razor.Design" Version="2.2.0" PrivateAssets="All" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="2.2.4" />
    <DotNetCliToolReference Include="Microsoft.EntityFrameworkCore.Tools.DotNet" Version="2.0.3" />

  </ItemGroup>

</Project>

回答1:

How to fix this

For Linux and macOS, add a line to your shell's configuration:

• bash/zsh:

  export PATH="$PATH:$HOME/.dotnet/tools/"
  

• csh/tcsh:

  set path = ($path $HOME/.dotnet/tools/)
  

When you start a new shell/terminal (or the next time you log in) dotnet ef should work.

For Windows:

See this question on how to add to the PATH environment variable.

You need to add %USERPROFILE%\.dotnet\tools to the PATH.

What's going on?

The .NET Core 3.0 (preview) version of this failure is much more illuminating:

$ dotnet ef
Could not execute because the specified command or file was not found.
Possible reasons for this include:
  * You misspelled a built-in dotnet command.
  * You intended to execute a .NET Core program, but dotnet-ef does not exist.
  * You intended to run a global tool, but a dotnet-prefixed executable with this name could not be found on the PATH.

The second and the third one both refer to dotnet trying to find a dotnet-ef command but can't find it. As the third point says, dotnet-ef is not in your path.

Here's what the docs say:

Global Tools can be installed in the default directory or in a specific location. The default directories are:

OS Path

Linux/macOS $HOME/.dotnet/tools

Windows %USERPROFILE%\.dotnet\tools

So, you should add $HOME/.dotnet/tools/ to your $PATH.

But also note this part from docs:

These locations are added to the user's path when the SDK is first run, so Global Tools installed there can be called directly.

So, it sounds like something went wrong. If you installed using a manual tarball, the SDK screwed up and you should report this bug to Microsoft. If you use a distribution package, they screwed up and you should report this as a bug to them.

回答2:

In my case, the tools folder didn't exist inside %USERPROFILE%\.dotnet\ so I had to run the command dotnet tool install --global dotnet-ef to install dotnet ef. Then I was able to run dotnet ef...

This was the result of the above install command:

回答3:

Sometimes when you install a new version of dotnet sdk, it hits the PATH.

You have to manually add the folder .dotnet/tools from your home directory to PATH.

回答4:

For those who encountered the issue after updating their Visual Studio or .NET Core package this is due to updates made in .NET Core 3 by removing dotnet ef from .NET Core and making it a separate package which can be installed via:

dotnet tool install -g dotnet-ef

For reference see this answer and this breaking change

回答5:

When you install a new version of .NET this one worked for me:

dotnet tool install --global dotnet-ef --version 3.0.1

来源：https://stackoverflow.com/questions/56862089/cannot-find-command-dotnet-ef