实体框架代码优先迁移失败，更新数据库

Question

我是新的EF代码。我从https://docs.microsoft.com/tr-tr/aspnet/mvc/overview/getting-started/getting-started-with-ef-using-mvc/migrations-and-deployment-with-the-entity-framework-in-an-asp-net-mvc-application学习当我写update-database时，我收到了这个错误：

  

指定＆＃39; -Verbose＆＃39;用于查看正在应用的SQL语句的标志   到目标数据库。应用显式迁移：   [201806161013068_ColumnFirstName]。应用显式迁移：   201806161013068_ColumnFirstName。警告：更改任何部分   对象名称可能会破坏脚本和存储过程。运行种子   方法。 System.Reflection.TargetException：非静态方法需要   目标。在   System.Reflection.RuntimeMethodInfo.CheckConsistency（Object target）
  在System.Reflection.RuntimeMethodInfo.InvokeArgumentsCheck（Object   obj，BindingFlags invokeAttr，Binder binder，Object []参数，   文化信息文化）   System.Reflection.RuntimeMethodInfo.Invoke（Object obj，BindingFlags   invokeAttr，Binder binder，Object []参数，CultureInfo文化）
  在System.Reflection.RuntimePropertyInfo.GetValue（Object obj，   BindingFlags invokeAttr，Binder binder，Object [] index，CultureInfo   system.Reflection.RuntimePropertyInfo.GetValue（Object。）   obj，Object [] index）at   System.Data.Entity.Core.Objects.ELinq.QueryParameterExpression.TryGetFieldOrPropertyValue（MemberExpression   我，对象实例，对象＆amp; memberValue）at   System.Data.Entity.Core.Objects.ELinq.QueryParameterExpression.TryEvaluatePath（表达式   表达式，ConstantExpression＆amp; constantExpression）   System.Data.Entity.Core.Objects.ELinq.QueryParameterExpression.EvaluateParameter（对象[]   争论   System.Data.Entity.Core.Objects.ELinq.ELinqQueryState.GetExecutionPlan（可空1 forMergeOption) at System.Data.Entity.Core.Objects.ObjectQuery 1＆LT;＆GT; c__DisplayClass7.b__6（）   在   System.Data.Entity.Core.Objects.ObjectContext.ExecuteInTransaction [T]（Func键1 func, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction, Boolean releaseConnectionOnSuccess) at System.Data.Entity.Core.Objects.ObjectQuery 1＆LT;＆GT; c__DisplayClass7.b__5（）   在   System.Data.Entity.Infrastructure.DbExecutionStrategy.Execute [TResult]（Func键1 operation) at System.Data.Entity.Core.Objects.ObjectQuery 1.GetResults（可空1 forMergeOption) at System.Data.Entity.Core.Objects.ObjectQuery 1..GetEnumerator＆GT; b__0（）   在System.Data.Entity.Internal.LazyEnumerator 1.MoveNext() at System.Linq.Enumerable.SingleOrDefault[TSource](IEnumerable 1来源）   在   System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.b__2 [TResult]（IEnumerable的1 sequence) at System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.ExecuteSingle[TResult](IEnumerable 1   查询，表达式queryRoot）at   System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.System.Linq.IQueryProvider.Execute [TResult]（式   表达）at   System.Data.Entity.Internal.Linq.DbQueryProvider.Execute [TResult]（式   表达）at   System.Linq.Queryable.SingleOrDefault [TSource]（IQueryable的1 source)
at ContosoUniversity.Migrations.Configuration.Seed(SchoolContext context) in C:\Users\Bengisu\source\repos\ContosoUniversity\ContosoUniversity\Migrations\Configuration.cs:line 119 at System.Data.Entity.Migrations.DbMigrationsConfiguration 1.OnSeed（的DbContext   System.Data.Entity.Migrations.DbMigrator.SeedDatabase（）上下文）   在   System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.SeedDatabase（）   在System.Data.Entity.Migrations.DbMigrator.Upgrade（IEnumerable 1 pendingMigrations, String targetMigrationId, String lastMigrationId)
at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.Upgrade(IEnumerable 1   pendingMigrations，String targetMigrationId，String lastMigrationId）
  在System.Data.Entity.Migrations.DbMigrator.UpdateInternal（String   targetMigration）   System.Data.Entity.Migrations.DbMigrator＆LT;＆GT; c__DisplayClasse.b__d（）   在   System.Data.Entity.Migrations.DbMigrator.EnsureDatabaseExists（动作   mustSucceedToKeepDatabase）at   System.Data.Entity.Migrations.Infrastructure.MigratorBase.EnsureDatabaseExists（动作   mustSucceedToKeepDatabase）at   System.Data.Entity.Migrations.DbMigrator.Update（字符串   targetMigration）   System.Data.Entity.Migrations.Infrastructure.MigratorBase.Update（字符串   targetMigration）   System.Data.Entity.Migrations.Design.ToolingFacade.UpdateRunner.RunCore（）   在System.Data.Entity.Migrations.Design.ToolingFacade.BaseRunner.Run（）   非静态方法需要目标。

第119行

，

var eInDb = context.Enrollments.Where(s => s.Student.ID == e.Student.ID
                  && s.Course.CourseID == e.CourseID).SingleOrDefault();

我的Configuration.cs：

internal sealed class Configuration : DbMigrationsConfiguration<ContosoUniversity.Data_Access_Layer.SchoolContext>
    {
        public Configuration()
        {
            AutomaticMigrationsEnabled = false;
        }

        protected override void Seed(SchoolContext context)
        {
            //  This method will be called after migrating to the latest version.

            //  You can use the DbSet<T>.AddOrUpdate() helper extension method 
            //  to avoid creating duplicate seed data.
            var students = new List<Student>
            {
                new Student { FirstMidName = "Carson",   LastName = "Alexander",
                    EnrollmentDate = DateTime.Parse("2010-09-01") },
                new Student { FirstMidName = "Meredith", LastName = "Alonso",
                    EnrollmentDate = DateTime.Parse("2012-09-01") },
                new Student { FirstMidName = "Arturo",   LastName = "Anand",
                    EnrollmentDate = DateTime.Parse("2013-09-01") },
                new Student { FirstMidName = "Gytis",    LastName = "Barzdukas",
                    EnrollmentDate = DateTime.Parse("2012-09-01") },
                new Student { FirstMidName = "Yan",      LastName = "Li",
                    EnrollmentDate = DateTime.Parse("2012-09-01") },
                new Student { FirstMidName = "Peggy",    LastName = "Justice",
                    EnrollmentDate = DateTime.Parse("2011-09-01") },
                new Student { FirstMidName = "Laura",    LastName = "Norman",
                    EnrollmentDate = DateTime.Parse("2013-09-01") },
                new Student { FirstMidName = "Nino",     LastName = "Olivetto",
                    EnrollmentDate = DateTime.Parse("2005-08-11") }
            };
            students.ForEach(s => context.Students.AddOrUpdate(p => p.LastName, s));
            context.SaveChanges();

            var courses = new List<Course>
            {
                new Course {CourseID = 1050, Title = "Chemistry",      Credits = 3, },
                new Course {CourseID = 4022, Title = "Microeconomics", Credits = 3, },
                new Course {CourseID = 4041, Title = "Macroeconomics", Credits = 3, },
                new Course {CourseID = 1045, Title = "Calculus",       Credits = 4, },
                new Course {CourseID = 3141, Title = "Trigonometry",   Credits = 4, },
                new Course {CourseID = 2021, Title = "Composition",    Credits = 3, },
                new Course {CourseID = 2042, Title = "Literature",     Credits = 4, }
            };
            courses.ForEach(s => context.Courses.AddOrUpdate(p => p.Title, s));
            context.SaveChanges();

            var enrollments = new List<Enrollment>
            {
                new Enrollment {
                    StudentID = students.Single(s => s.LastName == "Alexander").ID,
                    CourseID = courses.Single(c => c.Title == "Chemistry" ).CourseID,
                    Grade = Grade.A
                },
                 new Enrollment {
                    StudentID = students.Single(s => s.LastName == "Alexander").ID,
                    CourseID = courses.Single(c => c.Title == "Microeconomics" ).CourseID,
                    Grade = Grade.C
                 },
                 new Enrollment {
                    StudentID = students.Single(s => s.LastName == "Alexander").ID,
                    CourseID = courses.Single(c => c.Title == "Macroeconomics" ).CourseID,
                    Grade = Grade.B
                 },
                 new Enrollment {
                     StudentID = students.Single(s => s.LastName == "Alonso").ID,
                    CourseID = courses.Single(c => c.Title == "Calculus" ).CourseID,
                    Grade = Grade.B
                 },
                 new Enrollment {
                     StudentID = students.Single(s => s.LastName == "Alonso").ID,
                    CourseID = courses.Single(c => c.Title == "Trigonometry" ).CourseID,
                    Grade = Grade.B
                 },
                 new Enrollment {
                    StudentID = students.Single(s => s.LastName == "Alonso").ID,
                    CourseID = courses.Single(c => c.Title == "Composition" ).CourseID,
                    Grade = Grade.B
                 },
                 new Enrollment {
                    StudentID = students.Single(s => s.LastName == "Anand").ID,
                    CourseID = courses.Single(c => c.Title == "Chemistry" ).CourseID
                 },
                 new Enrollment {
                    StudentID = students.Single(s => s.LastName == "Anand").ID,
                    CourseID = courses.Single(c => c.Title == "Microeconomics").CourseID,
                    Grade = Grade.B
                 },
                new Enrollment {
                    StudentID = students.Single(s => s.LastName == "Barzdukas").ID,
                    CourseID = courses.Single(c => c.Title == "Chemistry").CourseID,
                    Grade = Grade.B
                 },
                 new Enrollment {
                    StudentID = students.Single(s => s.LastName == "Li").ID,
                    CourseID = courses.Single(c => c.Title == "Composition").CourseID,
                    Grade = Grade.B
                 },
                 new Enrollment {
                    StudentID = students.Single(s => s.LastName == "Justice").ID,
                    CourseID = courses.Single(c => c.Title == "Literature").CourseID,
                    Grade = Grade.B
                 }
            };

            foreach(Enrollment e in enrollments)
            {
                var eInDb = context.Enrollments.Where(s => s.Student.ID == e.Student.ID
                  && s.Course.CourseID == e.CourseID).SingleOrDefault();

                //if the enrollment is not found in the database
                if (eInDb == null)
                {
                    context.Enrollments.Add(e);
                }
            }
            context.SaveChanges();
        }
    }
}

使用-verbose选项：

  

PM＆GT; Update-Database -Verbose使用StartUp项目   ＆＃39; ContosoUniversity＆＃39 ;.使用NuGet项目＆＃39; ContosoUniversity＆＃39;。指定   ＆＃39; -Verbose＆＃39;用于查看正在应用于的SQL语句的标志   目标数据库。目标数据库是：＆＃39; ContosoUniversity2＆＃39; （数据源：   （LocalDb）\ v11.0，Provider：System.Data.SqlClient，Origin：   组态）。没有待定的显式迁移。运行种子方法。   System.Reflection.TargetException：非静态方法需要一个   目标。在   System.Reflection.RuntimeMethodInfo.CheckConsistency（Object target）
  在System.Reflection.RuntimeMethodInfo.InvokeArgumentsCheck（Object   obj，BindingFlags invokeAttr，Binder binder，Object []参数，   文化信息文化）   System.Reflection.RuntimeMethodInfo.Invoke（Object obj，BindingFlags   invokeAttr，Binder binder，Object []参数，CultureInfo文化）
  在System.Reflection.RuntimePropertyInfo.GetValue（Object obj，   BindingFlags invokeAttr，Binder binder，Object [] index，CultureInfo   system.Reflection.RuntimePropertyInfo.GetValue（Object。）   obj，Object [] index）at   System.Data.Entity.Core.Objects.ELinq.QueryParameterExpression.TryGetFieldOrPropertyValue（MemberExpression   我，对象实例，对象＆amp; memberValue）at   System.Data.Entity.Core.Objects.ELinq.QueryParameterExpression.TryEvaluatePath（表达式   表达式，ConstantExpression＆amp; constantExpression）   System.Data.Entity.Core.Objects.ELinq.QueryParameterExpression.EvaluateParameter（对象[]   争论   System.Data.Entity.Core.Objects.ELinq.ELinqQueryState.GetExecutionPlan（可空1 forMergeOption) at System.Data.Entity.Core.Objects.ObjectQuery 1＆LT;＆GT; c__DisplayClass7.b__6（）   在   System.Data.Entity.Core.Objects.ObjectContext.ExecuteInTransaction [T]（Func键1 func, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction, Boolean releaseConnectionOnSuccess) at System.Data.Entity.Core.Objects.ObjectQuery 1＆LT;＆GT; c__DisplayClass7.b__5（）   在   System.Data.Entity.Infrastructure.DbExecutionStrategy.Execute [TResult]（Func键1 operation) at System.Data.Entity.Core.Objects.ObjectQuery 1.GetResults（可空1 forMergeOption) at System.Data.Entity.Core.Objects.ObjectQuery 1..GetEnumerator＆GT; b__0（）   在System.Data.Entity.Internal.LazyEnumerator 1.MoveNext() at System.Linq.Enumerable.SingleOrDefault[TSource](IEnumerable 1来源）   在   System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.b__2 [TResult]（IEnumerable的1 sequence) at System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.ExecuteSingle[TResult](IEnumerable 1   查询，表达式queryRoot）at   System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.System.Linq.IQueryProvider.Execute [TResult]（式   表达）at   System.Data.Entity.Internal.Linq.DbQueryProvider.Execute [TResult]（式   表达）at   System.Linq.Queryable.SingleOrDefault [TSource]（IQueryable的1 source)
at ContosoUniversity.Migrations.Configuration.Seed(SchoolContext context) in C:\Users\Bengisu\source\repos\ContosoUniversity\ContosoUniversity\Migrations\Configuration.cs:line 119 at System.Data.Entity.Migrations.DbMigrationsConfiguration 1.OnSeed（的DbContext   System.Data.Entity.Migrations.DbMigrator.SeedDatabase（）上下文）   在   System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.SeedDatabase（）   在System.Data.Entity.Migrations.DbMigrator.Upgrade（IEnumerable 1 pendingMigrations, String targetMigrationId, String lastMigrationId)
at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.Upgrade(IEnumerable 1   pendingMigrations，String targetMigrationId，String lastMigrationId）
  在System.Data.Entity.Migrations.DbMigrator.UpdateInternal（String   targetMigration）   System.Data.Entity.Migrations.DbMigrator＆LT;＆GT; c__DisplayClasse.b__d（）   在   System.Data.Entity.Migrations.DbMigrator.EnsureDatabaseExists（动作   mustSucceedToKeepDatabase）at   System.Data.Entity.Migrations.Infrastructure.MigratorBase.EnsureDatabaseExists（动作   mustSucceedToKeepDatabase）at   System.Data.Entity.Migrations.DbMigrator.Update（字符串   targetMigration）   System.Data.Entity.Migrations.Infrastructure.MigratorBase.Update（字符串   targetMigration）   System.Data.Entity.Migrations.Design.ToolingFacade.UpdateRunner.RunCore（）   在System.Data.Entity.Migrations.Design.ToolingFacade.BaseRunner.Run（）   非静态方法需要目标。

Answer 1

正在收到此特定错误。原来是种子数据中有关用户创建的代码。

请密切注意ApplicationUser.UserName-我用破折号表示它无法创建用户。