// @nuget: EntityFramework

​

​

using System;

using System.Linq;

using System.Linq.Expressions;

using System.Data.Entity;

using System.Collections.Generic;

using LinqKit;

​

public class Program

{

    public static void Main()

    {

        using (var ctx = new zEntityFrameworkContext())

        {

            var Abbreviation1 = new Abbreviation() { ID = 1, Description = "A1", RecordStatusID = 1 };

            var Abbreviation2 = new Abbreviation() { ID = 2, Description = "A2", RecordStatusID = 2 };

​

            ctx.Abbreviation_XRef.Add(Abbreviation1);

            ctx.Abbreviation_XRef.Add(Abbreviation2);

​

            var ContactAbbreviation1 = new ContactAbbreviation() { ID = 1, ContactID = 1, AbbreviationID = 1, RecordStatusID = 1 };

            var ContactAbbreviation2 = new ContactAbbreviation() { ID = 2, ContactID = 1, AbbreviationID = 2, RecordStatusID = 1 };

            ctx.ContactAbbreviations.Add(ContactAbbreviation1);

            ctx.ContactAbbreviations.Add(ContactAbbreviation2);

​

            ctx.SaveChanges();

        }

        using (var ctx = new zEntityFrameworkContext())

        {

            ContactAbbreviationsFilter caFilter = new ContactAbbreviationsFilter

            {

                RecordStatusID = 1

            };

​

            AbbreviationFilter aFilter = new AbbreviationFilter

            {

                RecordStatusID = 2 

            };

​

​

            Expression<Func<ContactAbbreviation, bool>> subPredicate = x => aFilter.WhereClause().Invoke(x.Abbreviation_XRef);

            List<ContactAbbreviation> contactAbbreviations = ctx.ContactAbbreviations

                                                                .Include("Abbreviation_XRef")

                                                                .Where(subPredicate.Expand())

                                                                //.Where(x => x.Abbreviation_XRef.RecordStatusID == 2)

                                                                .ToList();

​

            FiddleHelper.WriteTable(contactAbbreviations);

        }

    }

    public interface IBaseTable

    {

        int ID { get; set; }

        int RecordStatusID { get; set; }

    }

​

    public class BaseTable

    {

        public int ID { get; set; }

        public int RecordStatusID { get; set; }

    }

    public class BaseFilter {

        public int? ID { get; set; }

        public int? RecordStatusID { get; set; }

​

        public Expression<Func<T, bool>> WhereClause<T>()

            where T : class, IBaseTable

        {

            int? ID = this.ID;

            int? RecordStatusID = this.RecordStatusID;

​

            ExpressionStarter<T> predicate = PredicateBuilder.New<T>(true);

​

            if (ID != null)

                predicate = predicate.And(x => x.ID == ID);

​

            if (RecordStatusID != null)

                predicate = predicate.And(x => x.RecordStatusID == RecordStatusID);

​

            return predicate;

        }

    }

    public class ContactAbbreviationsFilter : BaseFilter

    {

        public int? ContactID { get; set; }

        public int? AbbreviationID { get; set; }

​

        public Expression<Func<ContactAbbreviation, bool>> WhereClause()

        {

            int? ContactID = this.ContactID;

            int? AbbreviationID = this.AbbreviationID;

​

            ExpressionStarter<ContactAbbreviation> predicate = WhereClause();

​

            if (ContactID != null)

                predicate = predicate.And(x => x.ContactID == ContactID);

​

            if (AbbreviationID != null)

                predicate = predicate.And(x => x.AbbreviationID == AbbreviationID);

​

            return predicate;

        }

    }

    public class AbbreviationFilter : BaseFilter

    {

        public string Description { get; set; }

​

        public Expression<Func<Abbreviation, bool>> WhereClause()

        {

            string Description = this.Description;

​

            ExpressionStarter<Abbreviation> predicate = WhereClause();

​

            if (!string.IsNullOrEmpty(Description))

                predicate = predicate.And(x => x.Description == Description);

​

            return predicate;

        }

    }

    public class zEntityFrameworkContext : DbContext

    {

        public zEntityFrameworkContext() : base(FiddleHelper.GetConnectionStringSqlServer())

            {

            }

​

        public DbSet<ContactAbbreviation> ContactAbbreviations { get; set; }

        public DbSet<Abbreviation> Abbreviation_XRef { get; set; }

    }

    public class ContactAbbreviation

    {

        public int ID { get; set; }

        public int ContactID { get; set; }

        public int AbbreviationID { get; set; }

        public int RecordStatusID { get; set; }

​

        public Abbreviation Abbreviation_XRef { get; set; }

    }

​

    public class Abbreviation

    {

        public int ID { get; set; }

        public string Description { get; set; }

        public int RecordStatusID { get; set; }

    }

}