c# - EF Core 1.1 到 WebApi Core - 添加迁移失败

Question

我想我的所有依赖项都可以正常运行 1.1，但是当我尝试按照此处的步骤操作时 https://learn.microsoft.com/en-us/ef/core/get-started/aspnetcore/new-db我在运行 Add-Migration 命令时遇到错误。

PM> 添加迁移 InitialState

在启动类“Startup”上调用方法“ConfigureServices”时发生错误。

Consider using IDbContextFactory to override the initialization of theDbContext at design-time. Error: This method could not find a usersecret ID because the application’s entry assembly is not set. Tryusing the “.AddUserSecrets(Assembly assembly)” method instead. Noparameterless constructor was found on ‘ApplicationDbContext’. Eitheradd a parameterless constructor to ‘ApplicationDbContext’ or add animplementation of ‘IDbContextFactory’ in the same assembly as‘ApplicationDbContext’.

我的 project.json 的相关部分:……

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

“tools”: {
“Microsoft.EntityFrameworkCore.Tools.DotNet”: “1.1.0-preview4-final”
},

我的 ApplicationDbContext 确实有构造函数:

public ApplicationDbContext(DbContextOptions options) : base(options)
 { }

我的 Startup.cs 确实有:

services.AddDbContext(options => options.UseSqlServer(Configuration.GetConnectionString(“DefaultConnection”)));

还能是什么？

Answer 1

此问题与 builder.AddUserSecrets() 有关称呼。要修复，请执行以下步骤:

1. 通过添加属性 [assembly: UserSecretsId("aspnet-TestApp-ce345b64-19cf-4972-b34f-d16f2e7976ed")] 将用户 secret 添加到程序集(而不仅仅是 project.json)到 Startup.cs

2. 在 Startup.cs 中替换 builder.AddUserSecrets()与 builder.AddUserSecrets<Startup>();

引用:InvalidOperationException: Could not find 'UserSecretsIdAttribute' on assembly