帶有 MySQL 的 EF6 - 日期時間中的格式異常

Question

我有這樣的數據庫編碼：

public class DBModel : DbContext
    {
        public DBModel()
            : base("name=DBModel")
        {
        }

        public virtual DbSet<Entry> Entries{ get; set; }
    }

    public class Entry
    {
        [Key]
        public int Id { get; set; }
        public DateTime EntryDate { get; set; }
        public string EntryContent { get; set; }
        public virtual Alarm Alarm { get; set; }
    }

    public class Alarm
    {
        [Key]
        public int AlarmId { get; set; }
        public DateTime AlarmDate { get; set; }
        public bool Enabled { get; set; }
    }

當我嘗試更新數據庫時，它以帶有此堆棧的 FormatException 結束：

System.FormatException: Nieprawidłowy format ciągu wejściowego.
   w System.Number.ParseDouble(String value, NumberStyles options, NumberFormatInfo numfmt)
   w System.Convert.ToDouble(String value)
   w MySql.Data.Entity.MySqlMigrationSqlGenerator.Generate(CreateIndexOperation op)
   w MySql.Data.Entity.MySqlMigrationSqlGenerator.Generate(IEnumerable`1 migrationOperations, String providerManifestToken)
   w System.Data.Entity.Migrations.DbMigrator.ExecuteOperations(String migrationId, VersionedModel targetModel, IEnumerable`1 operations, IEnumerable`1 systemOperations, Boolean downgrading, Boolean auto)
   w System.Data.Entity.Migrations.DbMigrator.AutoMigrate(String migrationId, VersionedModel sourceModel, VersionedModel targetModel, Boolean downgrading)
   w System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.AutoMigrate(String migrationId, VersionedModel sourceModel, VersionedModel targetModel, Boolean downgrading)
   w System.Data.Entity.Migrations.DbMigrator.Upgrade(IEnumerable`1 pendingMigrations, String targetMigrationId, String lastMigrationId)
   w System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.Upgrade(IEnumerable`1 pendingMigrations, String targetMigrationId, String lastMigrationId)
   w System.Data.Entity.Migrations.DbMigrator.UpdateInternal(String targetMigration)
   w System.Data.Entity.Migrations.DbMigrator.EnsureDatabaseExists(Action mustSucceedToKeepDatabase)
   w System.Data.Entity.Migrations.DbMigrator.Update(String targetMigration)
   w System.Data.Entity.Infrastructure.Design.Executor.Update.<>c__DisplayClass0_0.<.ctor>b__0()
   w System.Data.Entity.Infrastructure.Design.Executor.OperationBase.Execute(Action action)

EF 框架版本：6.4.4 MySQL 服務器版本：8.0.18 MySQL 插件：

• MySQL.Data v6.10.9
• MySQL.Data v6.10.9

如何解決？

Answer 1

This looks like a bug in MySql.Data.EntityFramework, caused by this line: https://github.com/mysql/mysql-connector-net/blob/f3b6ae6a416de898b25edc0062b25a2f6ea90291/EntityFramework/src/MySqlMigrationSqlGenerator.cs#L771

我猜_providerManifestToken包含類似"8.0"的字符串，但是您的程序在浮點數格式為8,0的語言環境（pl-PL？）中運行。 因此，對Convert.ToDouble的區域性敏感調用失敗。

您可以在https://bugs.mysql.com將其報告為錯誤並等待修復。

或者，可以將Thread.CurrentCulture設置為en-US以運行遷移（ Thread.CurrentThread.CurrentCulture = new CultureInfo("en-US"); ），然后再將其設置回來。