为什么命令 'add-migration' 不接受我在 project.json 中安装的包？

Question

安装 microsoft.entityframework.tools -Pre/ 和 microsoft.entityframework.sqlserver 后，在使用 add-migration "InitialCreate" 时，出现“构建失败”的错误。即使尝试显式构建项目，它也会失败。

这是错误：

1>------ Build started: Project: OdeToFood, Configuration: Debug Any CPU ------
1>  C:\Program Files\dotnet\dotnet.exe build "C:\Users\Nazaqat\Documents\Visual Studio 2015\Projects\OdeToFood\src\OdeToFood" --configuration Debug --no-dependencies
1>C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v14.0\DotNet\Microsoft.DotNet.Common.Targets(262,5): error : Can not find runtime target for framework '.NETCoreApp,Version=v1.0' compatible with one of the target runtimes: 'win10-x64, win81-x64, win8-x64, win7-x64'. Possible causes:
1>C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v14.0\DotNet\Microsoft.DotNet.Common.Targets(262,5): error : 1. The project has not been restored or restore failed - run `dotnet restore`
1>C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v14.0\DotNet\Microsoft.DotNet.Common.Targets(262,5): error : 2. The project does not list one of 'win10-x64, win81-x64, win8-x64, win7-x64' in the 'runtimes' section.
1>C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v14.0\DotNet\Microsoft.DotNet.Common.Targets(262,5): error : 3. You may be trying to publish a library, which is not supported. Use `dotnet pack` to distribute libraries.
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

我的Project.json 文件如下所示：

{

  "dependencies": {
    "Microsoft.AspNetCore.Diagnostics": "1.1.0",
    "Microsoft.AspNetCore.Mvc": "1.1.0",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.1.0",
    "Microsoft.AspNetCore.Server.IISIntegration.Tools": "1.0.0-preview2-final",
    "Microsoft.AspNetCore.Server.Kestrel": "1.1.0",
    "Microsoft.AspNetCore.StaticFiles": "1.1.0",
    "Microsoft.EntityFrameworkCore": "1.1.0",
    "Microsoft.EntityFrameworkCore.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.SqlServer": "1.1.0",
    "Microsoft.EntityFrameworkCore.Tools": "1.1.0-preview4-final",
    "Microsoft.Extensions.Configuration.FileExtensions": "1.1.0",
    "Microsoft.Extensions.Configuration.Json": "1.1.0",
    "Microsoft.Extensions.Logging.Console": "1.1.0",
    "Microsoft.NETCore.App": "1.1.0"
  },

  "tools": {
    "Microsoft.AspNetCore.Server.IISIntegration.Tools": "1.0.0-preview2-final",
    "Microsoft.EntityFrameworkCore.Tools": "1.1.0-preview4-final"
  },

  "frameworks": {
    "netcoreapp1.0": {
      "imports": [
        "dotnet5.6",
        "portable-net45+win8"
      ]
    }
  },

  "buildOptions": {
    "emitEntryPoint": true,
    "preserveCompilationContext": true
  },

  "runtimeOptions": {
    "configProperties": {
      "System.GC.Server": true
    }
  },

  "publishOptions": {
    "include": [
      "wwwroot",
      "web.config"
    ]
  },

  "scripts": {
    "postpublish": [ "dotnet publish-iis --publish-folder %publish:OutputPath% --framework %publish:FullTargetFramework%" ]
  }
}

在网上看了下，看到一个解决方案，就是在project.json文件中加入如下runtime部分——这样解决方案就构建成功了：

"runtimes": {
    "win10-x64": { }
  }

但是，在包管理器控制台中使用 'add migration "InitialCreate"' 时，我收到错误消息：

Cannot execute this command because Microsoft.EntityFrameworkCore.Design is not installed. Install the version of that package that matches the installed version of Microsoft.EntityFrameworkCore and try again. 

即使我在上述project.json 文件中已经安装了所有软件包。

Answer 1

我的 JSON 文件更改为下面的一个，使我的应用程序正常工作。我必须确保我拥有以下安装版本：

{
  "dependencies": {

    "Microsoft.AspNetCore.Diagnostics": "1.1.0",
    "Microsoft.AspNetCore.Mvc": "1.1.0",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.1.0",
    "Microsoft.AspNetCore.Server.IISIntegration.Tools": "1.1.0-preview4-final",
    "Microsoft.AspNetCore.Server.Kestrel": "1.1.0",
    "Microsoft.AspNetCore.StaticFiles": "1.1.0",
    "Microsoft.EntityFrameworkCore": "1.1.0",
    "Microsoft.EntityFrameworkCore.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.SqlServer": "1.1.0",
    "Microsoft.EntityFrameworkCore.Tools": "1.1.0-preview4-final",
    "Microsoft.Extensions.Configuration.FileExtensions": "1.1.0",
    "Microsoft.Extensions.Configuration.Json": "1.1.0",
    "Microsoft.Extensions.Logging.Console": "1.1.0",
    "Microsoft.Extensions.Logging.Debug": "1.0.0",
    "Microsoft.AspNetCore.Identity.EntityFrameworkCore": "1.0.0",
    "Microsoft.NETCore.App": {
      "type": "platform",
      "version": "1.1.0"
    },
    "Microsoft.EntityFrameworkCore.Tools.DotNet": "1.1.0-preview4-final",
    "Microsoft.AspNetCore.Razor.Tools": {
      "version": "1.0.0-preview2-final",
      "type": "build"
    }
    },



  "tools": {
    "Microsoft.AspNetCore.Server.IISIntegration.Tools": "1.1.0-preview4-final",
    "Microsoft.EntityFrameworkCore.Tools.DotNet": "1.1.0-preview4-final",
    "Microsoft.AspNetCore.Razor.Tools": "1.0.0-preview2-final"
  },

  "frameworks": {
    "netcoreapp1.0": {
      "imports": [
        "dotnet5.6",
        "portable-net45+win8"
      ]
    }
  },


  "buildOptions": {
    "emitEntryPoint": true,
    "preserveCompilationContext": true
  },

  "runtimeOptions": {
    "configProperties": {
      "System.GC.Server": true
    }
  },

  "publishOptions": {
    "include": [
      "wwwroot",
      "web.config"
    ]
  },

  "scripts": {
    "postpublish": [ "dotnet publish-iis --publish-folder %publish:OutputPath% --framework %publish:FullTargetFramework%" ]
  }
}

Answer 2

您还需要更新frameworks 部分以定位netcoreapp1.1

如果这不能帮助替换它：

"frameworks": {
  "netcoreapp1.1": {
    "dependencies": {
      "Microsoft.NETCore.App": {
        "type": "platform",
        "version": "1.1.0"
      }
    },
    "imports": "dnxcore50"
  }
}