namespace NHSample5.Domain
{
   public class Patient
   {
       public virtual int Id { get; set; }
       public virtual string FirstName { get; set; }
       public virtual string LastName { get; set; }
   }
}

using System.Collections.Generic;

namespace NHSample5.Domain
{
   public class Doctor
   {
       public virtual int Id { get; set; }
       public virtual string Name { get; set; }
       public virtual IList<Patient> Patients { get; set; }

       public Doctor()
       {
           Patients = new List<Patient>();
       }
   }
}

using NHibernate.Validator.Constraints;

namespace NHSample5.Domain
{
   public class Patient
   {
       public virtual int Id { get; set; }

       [Length(Min = 3, Max = 20,Message="طول نام باید بین 3 و 20 کاراکتر باشد")]
       public virtual string FirstName { get; set; }

       [Length(Min = 3, Max = 60, Message = "طول نام خانوادگی باید بین 3 و 60 کاراکتر باشد")]
       public virtual string LastName { get; set; }
   }
}

[NotNull]
[Pattern(Regex = "[A-Za-z0-9]+")]

using NHibernate.Validator.Cfg.Loquacious;
using NHSample5.Domain;

namespace NHSample5.Validation
{
   public class DoctorDef : ValidationDef<Doctor>
   {
       public DoctorDef()
       {
           Define(x => x.Name).LengthBetween(3, 50);
           Define(x => x.Patients).NotNullableAndNotEmpty();           
       }
   }
}

using NHSample5.Domain;
using NHibernate.Validator.Cfg.Loquacious;

namespace NHSample5.Validation
{
   public class PatientDef : ValidationDef<Patient>
   {
       public PatientDef()
       {
           Define(x => x.FirstName)
               .LengthBetween(3, 20)
               .WithMessage("طول نام باید بین 3 و 20 کاراکتر باشد");

           Define(x => x.LastName)
               .LengthBetween(3, 60)
               .WithMessage("طول نام خانوادگی باید بین 3 و 60 کاراکتر باشد");
       }
   }
}

       /// <summary>
       /// استفاده از اعتبار سنجی ویژه به صورت مستقیم
       /// در صورت استفاده از ویژگی‌ها
       /// </summary>
       static void WithoutConfiguringTheEngine()
       {
           //تعریف یک بیمار غیر معتبر
           var patient1 = new Patient() { FirstName = "V", LastName = "N" };
           var ve = new ValidatorEngine();
           var invalidValues = ve.Validate(patient1);
           if (invalidValues.Length == 0)
           {
               Console.WriteLine("patient1 is valid.");
           }
           else
           {
               Console.WriteLine("patient1 is NOT valid!");
               //نمایش پیغام‌های تعریف شده مربوط به هر فیلد
               foreach (var invalidValue in invalidValues)
               {
                   Console.WriteLine(
                       "{0}: {1}",
                       invalidValue.PropertyName,
                       invalidValue.Message);
               }
           }

           //تعریف یک بیمار معتبر بر اساس قیودات اعمالی
           var patient2 = new Patient() { FirstName = "وحید", LastName = "نصیری" };
           if (ve.IsValid(patient2))
           {
               Console.WriteLine("patient2 is valid.");
           }
           else
           {
               Console.WriteLine("patient2 is NOT valid!");
           }
       }

       public static ValidatorEngine GetFluentlyConfiguredEngine()
       {
           var vtor = new ValidatorEngine();
           var configuration = new FluentConfiguration();
           configuration
                   .Register(
                       Assembly
                         .GetExecutingAssembly()
                         .GetTypes()
                         .Where(t => t.Namespace.Equals("NHSample5.Validation"))
                         .ValidationDefinitions()
                    )
                   .SetDefaultValidatorMode(ValidatorMode.UseExternal);
           vtor.Configure(configuration);
           return vtor;
       }

       /// <summary>
       /// استفاده از اعتبار سنجی ویژه به صورت مستقیم
       /// در صورت تعریف آن‌ها با کمک
       /// ValidationDef
       /// </summary>
       static void WithConfiguringTheEngine()
       {
           var ve2 = VeConfig.GetFluentlyConfiguredEngine();
           var doctor1 = new Doctor() { Name = "S" };
           if (ve2.IsValid(doctor1))
           {
               Console.WriteLine("doctor1 is valid.");
           }
           else
           {
               Console.WriteLine("doctor1 is NOT valid!");
           }

           var patient1 = new Patient() { FirstName = "وحید", LastName = "نصیری" };
           if (ve2.IsValid(patient1))
           {
               Console.WriteLine("patient1 is valid.");
           }
           else
           {
               Console.WriteLine("patient1 is NOT valid!");
           }

           var doctor2 = new Doctor() { Name = "شمس", Patients = new List<Patient>() { patient1 } };
           if (ve2.IsValid(doctor2))
           {
               Console.WriteLine("doctor2 is valid.");
           }
           else
           {
               Console.WriteLine("doctor2 is NOT valid!");
           }
       }

       /// <summary>
       /// از این کانفیگ برای آغاز سشن فکتوری باید کمک گرفته شود
       /// </summary>
       /// <param name="nhConfiguration"></param>
       public static void BuildIntegratedFluentlyConfiguredEngine(ref Configuration nhConfiguration)
       {
           var vtor = new ValidatorEngine();
           var configuration = new FluentConfiguration();
           configuration
                   .Register(
                       Assembly
                         .GetExecutingAssembly()
                         .GetTypes()
                         .Where(t => t.Namespace.Equals("NHSample5.Validation"))
                         .ValidationDefinitions()
                    )
                   .SetDefaultValidatorMode(ValidatorMode.UseExternal)
                   .IntegrateWithNHibernate
                   .ApplyingDDLConstraints()
                   .And
                   .RegisteringListeners();
           vtor.Configure(configuration);

           //Registering of Listeners and DDL-applying here
           ValidatorInitializer.Initialize(nhConfiguration, vtor);           
       }

       SingletonCore()
       {
           Configuration cfg = DbConfig.GetConfig().BuildConfiguration();
           VeConfig.BuildIntegratedFluentlyConfiguredEngine(ref cfg);
           //با همان کانفیگ تنظیم شده برای اعتبار سنجی باید کار شروع شود
           _sessionFactory = cfg.BuildSessionFactory();        
       }

       /// <summary>
       /// استفاده از اعتبار سنجی یکپارچه و خودکار
       /// </summary>
       static void tryToSaveInvalidPatient()
       {
           using (Repository<Patient> repo = new Repository<Patient>())
           {
               try
               {
                   var patient1 = new Patient() { FirstName = "V", LastName = "N" };
                   repo.Save(patient1);
               }
               catch (InvalidStateException ex)
               {
                   Console.WriteLine("Validation failed!");
                   foreach (var invalidValue in ex.GetInvalidValues())
                       Console.WriteLine(
                           "{0}: {1}",
                           invalidValue.PropertyName,
                           invalidValue.Message);
                   log4net.LogManager.GetLogger("NHibernate.SQL").Error(ex);
               }
           }
       }

       /// <summary>
       /// استفاده از اعتبار سنجی یکپارچه و خودکار
       /// </summary>
       static void tryToSaveValidPatient()
       {
           using (Repository<Patient> repo = new Repository<Patient>())
           {
               var patient1 = new Patient() { FirstName = "Vahid", LastName = "Nasiri" };
               repo.Save(patient1);
           }
       }

       public static void CreateValidDb()
       {
           bool script = false;//آیا خروجی در کنسول هم نمایش داده شود 
           bool export = true;//آیا بر روی دیتابیس هم اجرا شود             
           bool dropTables = false;//آیا جداول موجود دراپ شوند

           Configuration cfg = DbConfig.GetConfig().BuildConfiguration();
           VeConfig.BuildIntegratedFluentlyConfiguredEngine(ref cfg);
           //با همان کانفیگ تنظیم شده برای اعتبار سنجی باید کار شروع شود

           new SchemaExport(cfg).Execute(script, export, dropTables);
       }

CREATE TABLE EmployeeJsonAttributes (
  Id int NOT NULL AUTO_INCREMENT,
  EmployeeId int NOT NULL,
  Attributes json DEFAULT NULL,
  PRIMARY KEY (Id),
  FOREIGN KEY (EmployeeId) REFERENCES EmployeeEav (Id) ON DELETE CASCADE
)

INSERT INTO EmployeeJsonAttributes VALUES (
101, 
  '{
  "name": "Jon",
    "lastName": "Doe",
    "dateOfBirth": "1989-01-01 10:10:10+05:30",
    "skills": [ "C#", "JS" ],
    "address":  {
  "country": "UK",
      "city": "London",
      "email": "jon.doe@example.com"
    }
  }'
)

INSERT INTO efcoresample.EmployeeJsonAttributes VALUES (
101, 
  JSON_OBJECT(
"name", "Jon", 
"lastName", "Doe",
"dateOfBirth", "1989-01-01 10:10:10+05:30",
"skills", JSON_ARRAY("C#", "JS"),
    "address", JSON_OBJECT(
  "country", "UK",
      "city", "London",
  "email", "jon.doe@example.com"
    )
  )
)

SELECT JSON_EXTRACT(Attributes, '$.address.country') as Country 
FROM EmployeeJsonAttributes
WHERE EmployeeId = 101;

-- Conutry
-- "UK"

SELECT Attributes -> '$.address.country' as Country 
FROM EmployeeJsonAttributes
WHERE EmployeeId = 101;

-- Conutry
-- "UK"

SELECT EmployeeId, Attributes ->> '$.DateOfBirth' AS BirthDate FROM EmployeeJsonAttributes
WHERE Attributes ->> '$.DateOfBirth' > DATE_SUB(CURRENT_DATE(), INTERVAL 25 YEAR)

// Fluent API
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity<Employee>(entity =>
    {
        entity.Property(e => e.Attributes).HasColumnType("json");
    });
}

// Data Annotations
[Column(TypeName = "json")]
public string Attributes { get; set; }

public class EmployeeJsonAttribute
{
    public int Id { get; set; }
    public virtual EmployeeEav Employee { get; set; }
    public int EmployeeId { get; set; }
    [Column(TypeName = "json")]
    public string Attributes { get; set; }
}

dbContext.EmployeeJsonAttributes.Add(new EmployeeJsonAttribute
{
    EmployeeId =  101,
    Attributes = JsonSerializer.Serialize(new
    {
        FirstName = "Sirwan",
        LastName = "Afifi",
        DateOfBirth = DateTime.Now.AddYears(-31)
    })
});

dbContext.SaveChanges();

var employee = dbContext.EmployeeJsonAttributes.Find(201);
Console.WriteLine(JsonSerializer.Deserialize<Employee>(employee.Attributes).DateOfBirth);

Create VIEW EmployeesView
AS
SELECT id,
       FirstName
FROM   Employees

using System.ComponentModel.DataAnnotations;

namespace EF_Sample04.Models
{
    [Table("EmployeesView")]
    public class EmployeesView
    {
        public int Id { set; get; }
        public string FirstName { set; get; }
    }
}

There is already an object named 'EmployeesView' in the database.

Database.SetInitializer<Sample04Context>(null);

Add-Migration Init -IgnoreChanges
Update-Database

using System.ComponentModel.DataAnnotations;
using System.Xml.Linq;

namespace EF_Sample04.Models
{
    public class MyXMLTable
    {
        public int Id { get; set; }

        [Column(TypeName = "xml")]
        public string XmlValue { get; set; }

        [NotMapped]
        public XElement XmlValueWrapper
        {
            get { return XElement.Parse(XmlValue); }
            set { XmlValue = value.ToString(); }
        }
    }
}

namespace EF_Sample04.Models
{
    public class ActivityType
    {
        public int UserId { set; get; }
        public int ActivityID { get; set; }
    }
}

using System.Data.Entity.ModelConfiguration;
using EF_Sample04.Models;

namespace EF_Sample04.Mappings
{
    public class ActivityTypeConfig : EntityTypeConfiguration<ActivityType>
    {
        public ActivityTypeConfig()
        {
            this.HasKey(x => new { x.ActivityID, x.UserId });
        }
    }
}

var activity1 = db.ActivityTypes.Find(4, 1);

using System.Collections.Generic;

namespace EF_Sample04.Models
{
    public class Employee
    {
        public int Id { set; get; }
        public string FirstName { get; set; }
        public string LastName { get; set; }

        //public int? ManagerID { get; set; }
        public virtual Employee Manager { get; set; }       
    }
}

using System.Data.Entity.ModelConfiguration;
using EF_Sample04.Models;

namespace EF_Sample04.Mappings
{
    public class EmployeeConfig : EntityTypeConfiguration<Employee>
    {
        public EmployeeConfig()
        {
            this.HasOptional(x => x.Manager)
                .WithMany()
                //.HasForeignKey(x => x.ManagerID)
                .WillCascadeOnDelete(false);
        }
    }
}

    public abstract class LongPollingAsyncResult<TResult> : IAsyncResult where TResult : class
    {
        #region - Fields -

        private AsyncCallback _callback;
        private TimeSpan _timoutSpan;
        private TimeSpan _intervalWaitSpan;

        #endregion

        #region - Properties -
        public Exception Exception { get; private set; }
    
        public TResult Result { get; private set; }
     
        public object SyncRoot { get; private set; }

        #endregion

        #region - Ctor -
      
        public LongPollingAsyncResult(AsyncCallback callback, object asyncState, int timeoutSeconds = 300, int intervalWaitMilliseconds = 500)
        {
            SyncRoot = new object();
            _callback = callback;
            AsyncState = asyncState;
            AsyncWaitHandle = new ManualResetEvent(IsCompleted);
            _timoutSpan = TimeSpan.FromSeconds(timeoutSeconds);
            _intervalWaitSpan = TimeSpan.FromMilliseconds(intervalWaitMilliseconds);

            ThreadPool.QueueUserWorkItem(new WaitCallback(LoopWithIntervalAndTimeout));
        }

        #endregion

        #region - Private Helper Methods -

        private void LoopWithIntervalAndTimeout(object input)
        {
            try
            {
                Stopwatch stopwatch = new Stopwatch();
                stopwatch.Start();
                while (!IsCompleted)
                {
                    if (stopwatch.Elapsed > _timoutSpan)
                        throw new TimeoutException();
                    
                    DoWork();

                    if (!IsCompleted)
                        Thread.Sleep(_intervalWaitSpan);
                }
            }
            catch (Exception e)
            {
                Complete(null, e);
            }
        }

        #endregion

        #region - Protected/Abstract Methods -
        protected void Complete(TResult result, Exception e = null, bool completedSynchronously = false)
        {
            lock (SyncRoot)
            {
                CompletedSynchronously = completedSynchronously;
                Result = result;
                Exception = e;
                IsCompleted = true;

                if (_callback != null)
                    _callback(this);
            }
        }
       
        protected abstract void DoWork();

        #endregion

        #region - Public Methods -
        
        public TResult WaitForResult()
        {
            if (!IsCompleted)
                AsyncWaitHandle.WaitOne();

            if (Exception != null)
            {
                if (Exception is TimeoutException && WebOperationContext.Current != null)
                    WebOperationContext.Current.OutgoingResponse.StatusCode = HttpStatusCode.RequestTimeout;

                throw Exception;
            }

            return Result;
        }

        #endregion

        #region - IAsyncResult Implementation -

        public object AsyncState { get; private set; }
        
        public WaitHandle AsyncWaitHandle { get; private set; }

        public bool CompletedSynchronously { get; private set; }
       
        public bool IsCompleted { get; private set; }

        #endregion
    }

[OperationContract]
public string GetNotification();

[OperationContract(AsyncPattern = true)]
public IAsyncResult BeginWaitNotification(AsyncCallback callback, object state);
 
public string EndWaitNotification(IAsyncResult result);

public class MyNotificationResult : LongPollingAsyncResult<string>
{
   protected override DoWork()
    {
        کد‌های مورد نظر را اینجا قرار دهید
        base.Complete(...)
    }
}

public IAsyncResult BeginWaitNotification(AsyncCallback callback, object state)
{
    return new MyNotificationResult(callback, state);
}
 
public string EndWaitNotification(IAsyncResult result)
{
    MyNotificationResult myResult = result as MyNotificationResult;
    if(myResult == null)
        throw new ArgumentException("result was of the wrong type!");
 
    myResult.WaitForResult();
    return myResult.Result;
}