执行实体框架迁移时出现以下错误
dotnet.exe:System.ArgumentNullException:Value不能为null。行:1 char:1
+ dotnet ef - enter code here
- startup-project ../Bloomerang.Web迁移添加AssessmentQuestions
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo:NotSpecified :( System.Argument ...不能为null。:String)[],RemoteException
+ FullyQualifiedErrorId:NativeCommandError
参数名称:connectionString
at Microsoft.EntityFrameworkCore.Utilities.Check.NotEmpty(String value,String parameterName)
at Microsoft.EntityFrameworkCore.SqlServerDbContextOptionsExtensions.UseSqlServer(DbContextOptionsBuilder optionsBuilder,String connectionString,Action`1 sqlServerOptionsAction)
at Bloomerang.Web.Startup.b__4_0(DbContextOptionsBuilder选项)
at Microsoft.Extensions.DependencyInjection.EntityFrameworkServiceCollectionExtensions.DbContextOptionsFactory [TContext](IServiceProvider applicationServiceProvider,Action`2 optionsAction)
at Microsoft.Extensions.DependencyInjection.ServiceProvider.ScopedCallSite.Invoke(ServiceProvider provider)
at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService(IServiceProvider provider,Type serviceType)
at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService [T](IServiceProvider provider)
at Microsoft.Extensions.DependencyInjection.ServiceProvider.ScopedCallSite.Invoke(ServiceProvider provider)
at Microsoft.Extensions.DependencyInjection.ServiceLookup.ClosedIEnumerableService.CallSite.Invoke(ServiceProvider provider)
at Microsoft.Extensions.DependencyInjection.ServiceProvider.TransientCallSite.Invoke(ServiceProvider provider)
at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService(IServiceProvider provider,Type serviceType)
at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService [T](IServiceProvider provider)
at Microsoft.EntityFrameworkCore.Design.DbContextOperations.FindContextTypes()
at Microsoft.EntityFrameworkCore.Design.DbContextOperations.FindContextType(String name)
at Microsoft.EntityFrameworkCore.Design.DbContextOperations.CreateContext(String contextType)
at Microsoft.EntityFrameworkCore.Design.MigrationsOperations.AddMigration(String name,String outputDir,String contextType)
at Microsoft.EntityFrameworkCore.Tools.Cli.MigrationsAddCommand.Execute(CommonOptions commonOptions,String name,String outputDir,String context,String environment,Action`1 记者)
at Microsoft.EntityFrameworkCore.Tools.Cli.MigrationsAddCommand。<> c__DisplayClass0_0.b__0()
at Microsoft.Extensions.CommandLineUtils.CommandLineApplication.Execute(String [] args)
at Microsoft.EntityFrameworkCore.Tools.Cli.Program.Main(String [] args)
值不能为空。
参数名称:connectionString
答案 0 :(得分:0)
让你的appsettings.json类似于:
{
"ConnectionStrings":
{
"DefaultConnection": "Server=(localdb)\\mssqllocaldb;Database=ContosoUniversity1;Trusted_Connection=true;MultipleActiveResultSets=true"
},
"Logging":
{
"IncludeScopes": false,
"LogLevel":
{
"Default": "Warning"
}
}
}