使用setup-dotnet@v4时dotnet publish报MSB1008错误的原因

项目工作流使用setup-dotnet@v1时构建与发布均正常；切换至setup-dotnet@v4后，dotnet publish命令出现MSB1008错误（提示仅能指定一个项目），切回v1则恢复正常。

报错详情 #

Run dotnet publish ./Project/Project.csproj -c Release -o C:\Program Files\dotnet/myapp/
MSBUILD : error MSB1008: Only one project can be specified.
    Full command line: 'C:\Program Files\dotnet\sdk\8.0.302\MSBuild.dll -maxcpucount -verbosity:m -nologo -restore -target:Publish --property:_IsPublishing=true -property:PublishDir=C:\Program -property:_CommandLineDefinedOutputPath=true -property:Configuration=Release -property:DOTNET_CLI_DISABLE_PUBLISH_AND_PACK_RELEASE=true ./Project/Project.csproj Files\dotnet/myapp/ -distributedlogger:Microsoft.DotNet.Tools.MSBuild.MSBuildLogger,C:\Program Files\dotnet\sdk\8.0.302\dotnet.dll*Microsoft.DotNet.Tools.MSBuild.MSBuildForwardingLogger,C:\Program Files\dotnet\sdk\8.0.302\dotnet.dll'
  Switches appended by response files:
Switch: Files\dotnet/myapp/

For switch syntax, type "MSBuild -help"
Error: Process completed with exit code 1.

相关工作流片段 #

- name: Set up .NET Core
        uses: actions/setup-dotnet@v4
        with:
          dotnet-version: '8.x' 

      - name: Build with dotnet
        run: dotnet build ./Project/Project.csproj --configuration Release

      - name: dotnet publish
        run: dotnet publish ./Project/Project.csproj -c Release -o ${{env.DOTNET_ROOT}}/myapp/

错误原因及解决方法 #

原因 #

• setup-dotnet@v4中，DOTNET_ROOT环境变量的值为C:\Program Files\dotnet，路径包含空格。
• 执行dotnet publish命令时，未对带空格的输出路径加引号，导致命令被解析为-o C:\Program Files\dotnet/myapp/，MSBuild将空格后的Files\dotnet/myapp/误认为是第二个项目参数，触发"仅能指定一个项目"的MSB1008错误。
• setup-dotnet@v1中DOTNET_ROOT可能指向无空格路径，或旧版dotnet CLI对参数空格处理更宽松，因此未出现问题。

解决方法 #

• 给输出路径添加双引号包裹，避免空格拆分参数：

  - name: dotnet publish
    run: dotnet publish ./Project/Project.csproj -c Release -o "${{env.DOTNET_ROOT}}/myapp/"
  

• 或者改用无空格的输出目录，比如：

  - name: dotnet publish
    run: dotnet publish ./Project/Project.csproj -c Release -o ./publish/
  

内容的提问来源于stack exchange，提问作者Tim