// Dynamic LINQ - stef

​

// @nuget: System.Linq.Dynamic.Core

// @nuget: Z.EntityFramework.Classic

​

using System;

using System.Collections.Generic;

using System.Linq;

using System.Data.Entity;

using System.Linq.Expressions;

using System.Linq.Dynamic.Core;

public class Program

{   

    public static void Main()

    {

        GenerateData();

        var context = new EntityContext();

        // Example 1: Strongly styped = normal LINQ

        var example1 = context.Customers

            .Where(c => c.City == "Paris");

        FiddleHelper.WriteTable(example1);

​

        // Example 2: Dynamic

        var example2 = context.Customers

            .Where("City == \"Paris\"")

            .ToList();

        FiddleHelper.WriteTable(example2);

        // Example 3: Dynamic

        string cityToSearch = "Paris";

        var example3 = context.Customers

            .Where("City == @0", cityToSearch)

            .ToList();

        FiddleHelper.WriteTable(example3);

    }

    public static void GenerateData()

    {

        List<Customer> list = new List<Customer>();

        list.Add(new Customer()

        {

            Name = "Terri Lee Duffy",

            CompanyName = "ABC",

            City = "Paris",

            Phone = "333-444444",

            Orders = new List<Order>()

            {

                new Order() { Date = DateTime.Today }

            }

        });

        list.Add(new Customer()

        {

            Name = "Janice Galvin",

            CompanyName = "XYZ",

            City = "London",

            Phone = "333-555555",

            Orders = new List<Order>()

            {

                new Order() { Date = DateTime.Today.AddDays(-25) },

                new Order() { Date = DateTime.Today.AddDays(-11) },

                new Order() { Date = DateTime.Today.AddDays(-7) },

                new Order() { Date = DateTime.Today }

            }

        });

​

        list.Add(new Customer()

        {

            Name = "Michael Raheem",

            CompanyName = "DEF",

            City = "New York",

            Phone = "111-555555",

            Orders = new List<Order>()

            {

                new Order() { Date = DateTime.Today.AddDays(-4) },

                new Order() { Date = DateTime.Today }

            }

        });

​

        list.Add(new Customer()

        {

            Name = "Michael Sullivan",

            CompanyName = "ABC",

            City = "Paris",

            Phone = "333-888888",

            Orders = new List<Order>()

            {

                new Order() { Date = DateTime.Today.AddDays(-35) },

                new Order() { Date = DateTime.Today.AddDays(-21) },

                new Order() { Date = DateTime.Today.AddDays(-17) },

                new Order() { Date = DateTime.Today.AddDays(-11) },

                new Order() { Date = DateTime.Today.AddDays(-4) },

                new Order() { Date = DateTime.Today }

            }

        });

​

        list.Add(new Customer()

        {

            Name = "Rebecca Bradley",

            CompanyName = "KLM",

            City = "Tokyo",

            Phone = "333-666666",

            Orders = new List<Order>()

            {

                new Order() { Date = DateTime.Today.AddDays(-21) },

                new Order() { Date = DateTime.Today.AddDays(-18) },

                new Order() { Date = DateTime.Today.AddDays(-10) },

                new Order() { Date = DateTime.Today.AddDays(-9) },

            }

        });

​

        using (var context = new EntityContext())

        {

            context.Customers.AddRange(list);

            context.SaveChanges();

        }

    }

    public class EntityContext : DbContext

    {

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

        {

​

        }

        public DbSet<Customer> Customers { get; set; }

        public DbSet<Order> Orders { get; set; }

    }

    public class Customer

    {

        public int CustomerID { get; set; }

        public string Name { get; set; }

        public string CompanyName { get; set; }

        public string City { get; set; }

        public string Phone { get; set; }

        public List<Order> Orders { get; set; }

    }

​

    public class Order

    {

        public int OrderID { get; set; }

        public DateTime Date { get; set; }

    }

}