使用Scaffold-DBContext设置数据库优先EF项目

Question

我有一个数据库，我正在尝试建立一个数据库第一个EF项目。 我的项目是一个使用.Net Core的Web API项目。 像我发出的命令是这样的：

Scaffold-DbContext "Server=Server\Instance;Database=MyDatabase;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models

但是，我收到以下错误：

Could not load file or assembly 'Microsoft.EntityFrameworkCore.Design' or one of its dependencies. The system cannot find the file specified.

System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.EntityFrameworkCore.Design' or one of its dependencies. The system cannot find the file specified.
File name: 'Microsoft.EntityFrameworkCore.Design'
   at System.Reflection.RuntimeAssembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
   at System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
   at System.Activator.CreateInstance(String assemblyString, String typeName, Boolean ignoreCase, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes, Evidence securityInfo, StackCrawlMark& stackMark)
   at System.Activator.CreateInstance(String assemblyName, String typeName, Boolean ignoreCase, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes)
   at System.AppDomain.CreateInstance(String assemblyName, String typeName, Boolean ignoreCase, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes)
   at System.AppDomain.CreateInstanceAndUnwrap(String assemblyName, String typeName, Boolean ignoreCase, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes)
   at System.AppDomain.CreateInstanceAndUnwrap(String assemblyName, String typeName, Boolean ignoreCase, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes)
   at Microsoft.EntityFrameworkCore.Tools.AppDomainOperationExecutor..ctor(String assembly, String startupAssembly, String projectDir, String contentRootPath, String dataDirectory, String rootNamespace, String environment)
   at Microsoft.EntityFrameworkCore.Tools.Commands.ProjectCommandBase.CreateExecutor()
   at Microsoft.EntityFrameworkCore.Tools.Commands.DbContextScaffoldCommand.Execute()
   at Microsoft.DotNet.Cli.CommandLine.CommandLineApplication.Execute(String[] args)
   at Microsoft.EntityFrameworkCore.Tools.Program.Main(String[] args)

此项目的依赖项如下：

  "dependencies": {
    "Microsoft.Extensions.Options.ConfigurationExtensions": "1.1.0",
    "Microsoft.NETCore.App": "1.1.0",
    "NETStandard.Library": "1.6.1",
    "Microsoft.ApplicationInsights.AspNetCore": "2.0.0",
    "Microsoft.AspNetCore.Mvc": "1.1.1",
    "Microsoft.AspNetCore.Routing": "1.1.0",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.1.0",
    "Microsoft.AspNetCore.Server.Kestrel": "1.1.0",
    "Microsoft.Extensions.Configuration.Json": "1.1.0",
    "Microsoft.Extensions.Logging": "1.1.0",
    "Microsoft.Extensions.Logging.Console": "1.1.0",
    "Microsoft.Extensions.Logging.Debug": "1.1.0",
    "Microsoft.EntityFrameworkCore": "1.1.0",
    "Microsoft.EntityFrameworkCore.SqlServer": "1.1.0",
    "Microsoft.EntityFrameworkCore.Tools": "1.1.0-msbuild3-final",
    "Microsoft.EntityFrameworkCore.SqlServer.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.Relational.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.Design": "1.1.0",
    "System.Collections.NonGeneric": "4.3.0",
    "Microsoft.AspNetCore.Hosting.Abstractions": "1.1.0"
  },

如您所见，它被引用。

有人能指出我在这个方向上正确的方向吗？

编辑：

在它之前的当前（完整）project.json：

{
  "dependencies": {
    "Microsoft.ApplicationInsights.AspNetCore": "2.0.0",
    "Microsoft.AspNetCore.Hosting.Abstractions": "1.1.0",
    "Microsoft.AspNetCore.Mvc": "1.1.1",
    "Microsoft.AspNetCore.Routing": "1.1.0",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.1.0",
    "Microsoft.AspNetCore.Server.Kestrel": "1.1.0",
    "Microsoft.EntityFrameworkCore": "1.1.0",
    "Microsoft.EntityFrameworkCore.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.Relational.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.SqlServer": "1.1.0",
    "Microsoft.EntityFrameworkCore.SqlServer.Design": "1.1.0",    
    "Microsoft.EntityFrameworkCore.Tools.DotNet": "1.1.0-preview4-final",
    "Microsoft.Extensions.Configuration.Json": "1.1.0",
    "Microsoft.Extensions.Logging": "1.1.0",
    "Microsoft.Extensions.Logging.Console": "1.1.0",
    "Microsoft.Extensions.Logging.Debug": "1.1.0",
    "Microsoft.Extensions.Options.ConfigurationExtensions": "1.1.0",
    "Microsoft.NETCore.App": "1.1.0",
    "NETStandard.Library": "1.6.1",
    "System.Collections.NonGeneric": "4.3.0"
  },

  "tools": {
    "Microsoft.AspNetCore.Server.IISIntegration.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
    }
  },

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

  "publishOptions": {
    "include": [
      "wwwroot",
      "**/*.cshtml",
      "appsettings.json",
      "web.config"
    ]
  },

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

使用此配置，我收到编译错误：

Can not find runtime target for framework '.NETCoreApp,Version=v1.0' compatible with one of the target runtimes: 'win10-x86, win81-x86, win8-x86, win7-x86'. Possible causes:   JourneyService  C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v14.0\DotNet\Microsoft.DotNet.Common.Targets  262 Build   

Answer 1

请执行以下步骤。

1. 将.Net Core SDK更新为最新的最新版本。 （对于新的1.0.0-preview2-1-003177 ）。 下载链接

2. 在gobal.json文件中更新.Net Core SDK版本

3. 在project.json frameworks部分更新netcoreapp版本

    "frameworks": { "netcoreapp1.1": { "imports": [ "dotnet5.6", "portable-net45+win8" ] } }, 

4. 将这些包添加到`project.json

    "Microsoft.EntityFrameworkCore.SqlServer.Design": { "version": "1.1.0", "type": "build" }, "Microsoft.EntityFrameworkCore.Tools": { "version": "1.1.0-preview4-final", "type": "build" } 

5. 更新project.json的工具部分并添加Microsoft.EntityFrameworkCore.Tools最新版本

    "tools": { "Microsoft.EntityFrameworkCore.Tools": "1.1.0-preview4-final" }, 

命令：

`Scaffold-DbContext "Server=Server\\Instance;Database=MyDatabase;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models`

完成project.json文件。

{
  "dependencies": {
    "Microsoft.ApplicationInsights.AspNetCore": "2.0.0",
    "Microsoft.AspNetCore.Hosting.Abstractions": "1.1.0",
    "Microsoft.AspNetCore.Mvc": "1.1.1",
    "Microsoft.AspNetCore.Routing": "1.1.0",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.1.0",
    "Microsoft.AspNetCore.Server.Kestrel": "1.1.0",
    "Microsoft.EntityFrameworkCore": "1.1.0",
    "Microsoft.EntityFrameworkCore.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.Relational.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.SqlServer": "1.1.0",
    "Microsoft.EntityFrameworkCore.Tools.DotNet": "1.1.0-preview4-final",
    "Microsoft.Extensions.Configuration.Json": "1.1.0",
    "Microsoft.Extensions.Logging": "1.1.0",
    "Microsoft.Extensions.Logging.Console": "1.1.0",
    "Microsoft.Extensions.Logging.Debug": "1.1.0",
    "Microsoft.Extensions.Options.ConfigurationExtensions": "1.1.0",
    "Microsoft.NETCore.App": {
      "version": "1.1.0",
      "type": "platform"
    },
    "NETStandard.Library": "1.6.1",
    "System.Collections.NonGeneric": "4.3.0",

    "Microsoft.EntityFrameworkCore.SqlServer.Design": {
      "version": "1.1.0",
      "type": "build"
    },
    "Microsoft.EntityFrameworkCore.Tools": {
      "version": "1.1.0-preview4-final",
      "type": "build"
    }
  },

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

  "frameworks": {
    "netcoreapp1.1": {
      "imports": [
        "dotnet5.6",
        "portable-net45+win8"
      ]
    }
  },

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

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

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

  "publishOptions": {
    "include": [
      "wwwroot",
      "**/*.cshtml",
      "appsettings.json",
      "web.config"
    ]
  },

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