c# - EF 迁移期间未找到所需属性 "type"

Question

针对 Azure SQL 数据库运行 EF 迁移时抛出以下错误:

System.TypeInitializationException: The type initializer for 'System.Data.SqlClient.SqlConnection' threw an exception. ---> System.TypeInitializationException: The type initializer for 'System.Data.SqlClient.SqlConnectionFactory' threw an exception. ---> System.TypeInitializationException: The type initializer for 'System.Data.SqlClient.SqlPerformanceCounters' threw an exception. ---> System.Configuration.ConfigurationErrorsException: Required attribute 'type' not found. (--DATA OMITTED FOR PRIVACY REASONS--)
   at System.Configuration.BaseConfigurationRecord.EvaluateOne(String[] keys, SectionInput input, Boolean isTrusted, FactoryRecord factoryRecord, SectionRecord sectionRecord, Object parentResult)
   at System.Configuration.BaseConfigurationRecord.Evaluate(FactoryRecord factoryRecord, SectionRecord sectionRecord, Object parentResult, Boolean getLkg, Boolean getRuntimeObject, Object& result, Object& resultRuntimeObject)
   at System.Configuration.BaseConfigurationRecord.GetSectionRecursive(String configKey, Boolean getLkg, Boolean checkPermission, Boolean getRuntimeObject, Boolean requestIsHere, Object& result, Object& resultRuntimeObject)
   at System.Configuration.BaseConfigurationRecord.GetSectionRecursive(String configKey, Boolean getLkg, Boolean checkPermission, Boolean getRuntimeObject, Boolean requestIsHere, Object& result, Object& resultRuntimeObject)
   at System.Configuration.BaseConfigurationRecord.GetSectionRecursive(String configKey, Boolean getLkg, Boolean checkPermission, Boolean getRuntimeObject, Boolean requestIsHere, Object& result, Object& resultRuntimeObject)
   at System.Configuration.BaseConfigurationRecord.GetSection(String configKey)
   at System.Configuration.ClientConfigurationSystem.System.Configuration.Internal.IInternalConfigSystem.GetSection(String sectionName)
   at System.Configuration.ConfigurationManager.GetSection(String sectionName)
   at System.Configuration.PrivilegedConfigurationManager.GetSection(String sectionName)
   at System.Diagnostics.DiagnosticsConfiguration.GetConfigSection()
   at System.Diagnostics.DiagnosticsConfiguration.Initialize()
   at System.Diagnostics.DiagnosticsConfiguration.get_SwitchSettings()
   at System.Diagnostics.Switch.InitializeConfigSettings()
   at System.Diagnostics.Switch.InitializeWithStatus()
   at System.Diagnostics.Switch.get_SwitchSetting()
   at System.Diagnostics.TraceSwitch.get_Level()
   at System.Data.ProviderBase.DbConnectionPoolCounters..ctor(String categoryName, String categoryHelp)
   at System.Data.SqlClient.SqlPerformanceCounters..ctor()
   at System.Data.SqlClient.SqlPerformanceCounters..cctor()
   --- End of inner exception stack trace ---
   at System.Data.SqlClient.SqlConnectionFactory..cctor()
   --- End of inner exception stack trace ---
   at System.Data.SqlClient.SqlConnection..cctor()
   --- End of inner exception stack trace ---
   at System.Data.SqlClient.SqlConnection..ctor()
   at System.Data.SqlClient.SqlClientFactory.CreateConnection()
   at System.Data.Entity.Internal.LazyInternalConnection.CreateConnectionFromProviderName(String providerInvariantName)
   at System.Data.Entity.Internal.LazyInternalConnection.InitializeFromConnectionStringSetting(ConnectionStringSettings appConfigConnection)
   at System.Data.Entity.Internal.LazyInternalConnection.Initialize()
   at System.Data.Entity.Internal.LazyInternalConnection.get_Connection()
   at System.Data.Entity.Internal.LazyInternalContext.get_Connection()
   at System.Data.Entity.Infrastructure.DbContextInfo..ctor(Type contextType, DbProviderInfo modelProviderInfo, AppConfig config, DbConnectionInfo connectionInfo)
   at System.Data.Entity.Migrations.DbMigrator..ctor(DbMigrationsConfiguration configuration, DbContext usersContext)
   at System.Data.Entity.Migrations.DbMigrator..ctor(DbMigrationsConfiguration configuration)
   at System.Data.Entity.Migrations.Design.MigrationScaffolder..ctor(DbMigrationsConfiguration migrationsConfiguration)
   at System.Data.Entity.Migrations.Design.ToolingFacade.ScaffoldRunner.Run()
   at System.AppDomain.DoCallBack(CrossAppDomainDelegate callBackDelegate)
   at System.AppDomain.DoCallBack(CrossAppDomainDelegate callBackDelegate)
   at System.Data.Entity.Migrations.Design.ToolingFacade.Run(BaseRunner runner)
   at System.Data.Entity.Migrations.Design.ToolingFacade.Scaffold(String migrationName, String language, String rootNamespace, Boolean ignoreChanges)
   at System.Data.Entity.Migrations.AddMigrationCommand.Execute(String name, Boolean force, Boolean ignoreChanges)
   at System.Data.Entity.Migrations.AddMigrationCommand.<>c__DisplayClass2.<.ctor>b__0()
   at System.Data.Entity.Migrations.MigrationsDomainCommand.Execute(Action command)
The type initializer for 'System.Data.SqlClient.SqlConnection' threw an exception.

错误是在我为我的应用程序启用跟踪后开始出现的。虽然我已经解决了这个问题，但我还是以问答的形式发布在这里，以防其他人遇到这个问题。

Answer 1

问题是由我们的跟踪事件监听器引起的。运行迁移时，只需注释掉 web.config/app.config 文件中的 Systems.Diagnostics 标记即可。

如果对您有帮助，请+1。