2017-09-04 298 views
5

我試圖添加我的第一個EF Core 2遷移。我有EF6遷移運行的解決方案,但現在我已經遷移到EF Core 2和.Net Core 2.0。當我運行此命令:試圖讓ef核心遷移工作遷移到.net core 2

dotnet ef migrations add InitialMigration 

我得到這個異常:

System.IO.FileNotFoundException: Could not load file or assembly 'netstandard, Version=2.0.0.0, Culture=neutral, 
PublicKeyToken=cc7b13ffcd2ddd51'. The system cannot find the file specified. 
File name: 'netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' 
    at System.Reflection.RuntimeAssembly.GetType(RuntimeAssembly assembly, String name, Boolean throwOnError, Boolean ignoreCase, ObjectHandleOnStack type, ObjectHandleOnStack keepAlive) 
    at System.Reflection.RuntimeAssembly.GetType(String name, Boolean throwOnError, Boolean ignoreCase) 
    at Microsoft.EntityFrameworkCore.Tools.ReflectionOperationExecutor..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.MigrationsListCommand.Execute() 
    at Microsoft.DotNet.Cli.CommandLine.CommandLineApplication.Execute(String[] args) 
    at Microsoft.EntityFrameworkCore.Tools.Program.Main(String[] args) 
Could not load file or assembly 'netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'. The system cannot find the file specified. 

我在Windows 10上運行從包管理器控制檯命令在Visual Studio 2017年v15.3我得到的嘗試從Windows命令行運行時出現相同的消息。啓動項目以及默認項目被設置爲包含數據庫上下文類的類庫。這是該項目的.csproj項目文件:

<Project Sdk="Microsoft.NET.Sdk"> 
    <PropertyGroup> 
    <TargetFramework>netcoreapp2.0</TargetFramework> 
    </PropertyGroup> 
    <ItemGroup> 
    <PackageReference Include="Analytics" Version="3.0.0" /> 
    <PackageReference Include="AWSSDK.Core" Version="3.3.17.6" /> 
    <PackageReference Include="AWSSDK.S3" Version="3.3.10.2" /> 
    <PackageReference Include="CoreCompat.System.Drawing.v2" Version="5.2.0-preview1-r131" /> 
    <PackageReference Include="HtmlAgilityPack" Version="1.5.1" /> 
    <PackageReference Include="ImageProcessor" Version="2.5.4" /> 
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="2.0.0" /> 
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer.Design" Version="2.0.0-preview1-final" /> 
    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="2.0.0" /> 
    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools.DotNet" Version="2.0.0" /> 
    <PackageReference Include="Newtonsoft.Json" Version="10.0.3" /> 
    <PackageReference Include="NLog.Extensions.Logging" Version="1.0.0-rtm-beta5" /> 
    <PackageReference Include="QRCoder" Version="1.2.9" /> 
    <PackageReference Include="System.Configuration.ConfigurationManager" Version="4.4.0" /> 
    <PackageReference Include="WindowsAzure.Storage" Version="8.4.0" /> 
    </ItemGroup> 
    <ItemGroup> 
    <DotNetCliToolReference Include="Microsoft.EntityFrameworkCore.Tools.DotNet" Version="1.0.0" /> 
    </ItemGroup> 
</Project> 

任何想法,我在做什麼錯了,或者我該如何解決問題?

回答

4
<DotNetCliToolReference Include="Microsoft.EntityFrameworkCore.Tools.DotNet" 
         Version="1.0.0" /> 

您需要更新到2.0.0版本。