asp.net核心和EF核心错误，同时添加迁移

在一个asp.net核心应用程序，我试图为EF代码拳头迁移。asp.net核心和EF核心错误，同时添加迁移

我得到了下面的错误，

An error occurred while calling method 'ConfigureServices' on startup class 'WebAppHandOn.Startup'. Consider using IDbContextFactory to override the initialization of the DbContext at design-time. Error: Could not load file or assembly 'Microsoft.AspNetCore.Routing, Version=1.0.1.0, Culture=neutral, PublicKeyToken=adb9793829ddae60' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)

No parameterless constructor was found on 'ApplicationDbContext'. Either add a parameterless constructor to 'ApplicationDbContext' or add an implementation of 'IDbContextFactory' in the same assembly as 'ApplicationDbContext'.

这里有不同的代码文件，

启动类

public void ConfigureServices(IServiceCollection services) 
{ 
    // Add framework services. 
    services.AddMvc(); 

    // Add EntityFramework's Identity support. 
    services.AddEntityFramework(); 

    // Add ApplicationDbContext. 
    services.AddDbContext<ApplicationDbContext>(options => options.UseSqlServer(Configuration["Data:DefaultConnection:ConnectionString"])); 
}

ApplicationDBContext类

public class ApplicationDbContext : DbContext { 
    #region Constructor 

    public ApplicationDbContext(DbContextOptions options) : base(options) 
    { 
    } 
    #endregion Constructor 

    #region Methods 
    protected override void OnModelCreating(ModelBuilder modelBuilder) 
    { 
     base.OnModelCreating(modelBuilder); 
    } 
    #endregion Methods 

    #region Properties 
    public DbSet<Item> Items { get; set; } 
    public DbSet<Comment> Comments { get; set; } 
    public DbSet<ApplicationUser> Users { get; set; } 
    #endregion Properties 
}

Project.json类

{ 
 
     "dependencies": { 
 
    "Microsoft.AspNetCore.Mvc": "1.0.0", 
 
    "Microsoft.AspNetCore.Server.IISIntegration": "1.0.0", 
 
    "Microsoft.AspNetCore.Server.Kestrel": "1.0.0", 
 
    "Microsoft.Extensions.Configuration.EnvironmentVariables": "1.0.0", 
 
    "Microsoft.Extensions.Configuration.FileExtensions": "1.0.0", 
 
    "Microsoft.Extensions.Configuration.Json": "1.0.0", 
 
    "Microsoft.Extensions.Logging": "1.0.0", 
 
    "Microsoft.Extensions.Logging.Console": "1.0.0", 
 
    "Microsoft.Extensions.Logging.Debug": "1.0.0", 
 
    "Microsoft.Extensions.Options.ConfigurationExtensions": "1.0.0", 
 
    "Microsoft.AspNetCore.Diagnostics": "1.0.0", 
 
    "Microsoft.AspNetCore.Routing": "1.0.0", 
 
    "Microsoft.AspNetCore.Authentication.JwtBearer": "1.0.0", 
 
    "Microsoft.AspNetCore.StaticFiles": "1.0.0", 
 
    "Microsoft.VisualStudio.Web.BrowserLink.Loader": "14.0.0", 
 
    "Newtonsoft.Json": "9.0.1", 
 
    "Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore": "1.0.0", 
 
    "Microsoft.AspNetCore.Identity.EntityFrameworkCore": "1.0.0", 
 
    "Microsoft.EntityFrameworkCore": "1.0.0", 
 
    "Microsoft.EntityFrameworkCore.SqlServer": "1.0.0", 
 
    "Microsoft.EntityFrameworkCore.Design": "1.0.0-preview2-final", 
 
    "TinyMapper": "2.0.8" 
 
    }, 
 

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

来源

2016-12-30 shazia perween

有可能你正在调用新的ApplicationDbContext（）; 因为乍一看似乎一切都很正常。 – Woot

发现此https://docs.microsoft.com/en-us/ef/core/miscellaneous/cli/dotnet 2/3的他们下来他们有这个问题的解决方案 – Woot

检查yourproject.csproj文件，在任何PackageReference标记删除任何预览版本，并重新安装稳定的版本与管理的NuGet包。希望有帮助

来源

2017-05-12 20:21:29

asp.net核心和EF核心错误，同时添加迁移

回答

相关问题