Question

我有一个有三层的应用程序。我正在使用EntityFramework 6.1并使用现有数据库编写第一个迁移代码。下面给出了三个层：

1. Presententation Layer ：ConceptuCodeFirstMigrationDemo 简单的控制台应用程序

数据层由Context和Initializer组成。代码如下：

     namespace ConceptuCodeFirstMigrationDemo.Data.DataContext
        {
          using System;
          using System.Data.Entity;
          using System.ComponentModel.DataAnnotations.Schema;
          using System.Linq;
          using ConceptuCodeFirstMigrationDemo.Domain;

    public partial class ConceptuContext : DbContext,IDisposable
    {
        public ConceptuContext()
            : base("name=ConceptuContext")
        {
        }
       public virtual DbSet<User> Users { get; set; }
       protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
                modelBuilder.Entity<User>()

                .WithRequired(e => e.User)
                .HasForeignKey(e => e.CreatedBy)
                .WillCascadeOnDelete(false);

         }
       }
      }

ConceptuInitializer.Cs

namespace ConceptuCodeFirstMigrationDemo.Data.DataContext
{
   public class ConceptuInitializer:      System.Data.Entity.CreateDatabaseIfNotExists<ConceptuContext>
    {
    }
}

的AppConfig：

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
    <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
  </configSections>
  <entityFramework>
    <contexts>

        <context type="ConceptuCodeFirstMigrationDemo.Data.DataContext.ConceptuContext, ConceptuCodeFirstMigrationDemo.Data">
          <databaseInitializer type="ConceptuCodeFirstMigrationDemo.Data.DataContext.ConceptuInitializer, ConceptuCodeFirstMigrationDemo.Data" />
        </context>
    </contexts>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
    <providers>
      <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
    </providers>
  </entityFramework>
  <connectionStrings>
    <add name="ConceptuContext" connectionString="data source=AMITABHA-PC;initial catalog=Conceptu;user id=sa;password=lovediya;MultipleActiveResultSets=True;App=EntityFramework" providerName="System.Data.SqlClient" />
  </connectionStrings>
</configuration>

域层：由实体类组成，例如用户

尝试使用Enable-Migrations启用迁移时编写新类展示 在程序集中找不到上下文类型＆＃39; ConceptuCodeFirstMigrationDemo＆＃39;。

尝试以下命令后：启用 - 迁移--ContextTypeName ConceptuCodeFirstMigrationDemo.Data.DataContext.ConceptuContext

这显示以下错误 上下文类型＆＃39; ConceptuCodeFirstMigrationDemo.Data.DataContext.ConceptuContext＆＃39;未在装配中找到＆＃39; ConceptuCodeFirstMigrationDemo＆＃39;。

尝试以下命令后启用 - 迁移ConceptuCodeFirstMigrationDemo.Data.DataContext.ConceptuContext

显示以下错误

启用 - 迁移：找不到接受参数＆＃39; ConceptuCodeFirstMigrationDemo.Data.DataContext.Concept的位置参数 uContext＆＃39 ;. 在线：1字符：18 +启用 - 迁移＆lt;＆lt;＆lt;＆lt; ConceptuCodeFirstMigrationDemo.Data.DataContext.ConceptuContext + CategoryInfo：InvalidArgument：（:) [Enable-Migrations]，ParameterBindingException + FullyQualifiedErrorId：PositionalParameterNotFound，启用 - 迁移

Answer 1

试试这个。

Enable-Migrations -ContextTypeName ConceptuCodeFirstMigrationDemo.Data.DataContext.ConceptuContext -ProjectName ConceptuCodeFirstMigrationDemo

启用迁移不起作用

1 个答案: