public class Rider
{
    public int Id { get; set; }
    public EquineBeast Mount { get; set; }
}

public enum EquineBeast
{
    Donkey,
    Mule,
    Horse,
    Unicorn
}

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder
        .Entity<Rider>()
        .Property(e => e.Mount)
        .HasConversion(
            v => v.ToString(),
            v => (EquineBeast)Enum.Parse(typeof(EquineBeast), v));
}

var converter = new ValueConverter<EquineBeast, string>(
    v => v.ToString(),
    v => (EquineBeast)Enum.Parse(typeof(EquineBeast), v));
modelBuilder
    .Entity<Rider>()
    .Property(e => e.Mount)
    .HasConversion(converter);

var converter = new EnumToStringConverter<EquineBeast>();
modelBuilder
    .Entity<Rider>()
    .Property(e => e.Mount)
    .HasConversion(converter);

modelBuilder
    .Entity<Rider>()
    .Property(e => e.Mount)
    .HasConversion<string>();

public class Rider
{
    public int Id { get; set; }

    [Column(TypeName = "nvarchar(24)")]
    public EquineBeast Mount { get; set; }
}

namespace DbConfig.Web.DataLayer.Context
{
    public class MyAppContext : DbContext
    {
      // …

        protected override void OnModelCreating(ModelBuilder builder)
        {
            var encryptedConverter = new ValueConverter<string, string>(
               convertToProviderExpression: v => new string(v.Reverse().ToArray()), // encrypt
               convertFromProviderExpression: v => new string(v.Reverse().ToArray()) // decrypt
            );

            // Custom application mappings
            builder.Entity<ConfigurationValue>(entity =>
            {
                entity.Property(e => e.Value).IsRequired().HasConversion(encryptedConverter);
            });
        }
    }
}

using System;

namespace Test
{
    [AttributeUsage(AttributeTargets.Property, Inherited = false, AllowMultiple = false)]
    public sealed class EncryptedAttribute : Attribute
    { }
}

namespace DbConfig.Web.DomainClasses
{
    public class ConfigurationValue
    {
        public int Id { get; set; }
        public string Key { get; set; }

        [Encrypted]
        public string Value { get; set; }
    }
}

namespace DbConfig.Web.DataLayer.Context
{
    public class MyAppContext : DbContext
    {
        protected override void OnModelCreating(ModelBuilder builder)
        {
            var encryptedConverter = new ValueConverter<string, string>(
               convertToProviderExpression: v => new string(v.Reverse().ToArray()), // encrypt
               convertFromProviderExpression: v => new string(v.Reverse().ToArray()) // decrypt
            );

            foreach (var entityType in builder.Model.GetEntityTypes())
            {
                foreach (var property in entityType.GetProperties())
                {
                    var attributes = property.PropertyInfo.GetCustomAttributes(typeof(EncryptedAttribute), false);
                    if (attributes.Any())
                    {
                        property.SetValueConverter(encryptedConverter);
                    }
                }
            }
        }

 Executed DbCommand (22ms) 
   [Parameters=[@p1='1', 
                @p0='.tset ot eulav wen A' (Nullable = false) (Size = 4000)],
CommandType='Text', CommandTimeout='180']
SET NOCOUNT ON;
UPDATE [Configurations] SET [Value] = @p0
WHERE [Id] = @p1;
SELECT @@ROWCOUNT;

 db.Set<ConfigurationValue>().Where(x => x.Value.EndsWith("world!"))

SELECT [x].[Id], [x].[Key], [x].[Value]
FROM [Configurations] AS [x]
WHERE RIGHT([x].[Value], LEN(N'world!')) = N'!dlrow'

using System;
using System.Linq;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Data.Entity;
using System.Data.Entity.Migrations;
using System.Data.Entity.ModelConfiguration;

namespace Sample
{
    public class BlogPost
    {
        public int Id { set; get; }

        [StringLength(maximumLength: 450, MinimumLength = 1), Required]
        public string Title { set; get; }

        [MaxLength]
        public string Body { set; get; }

        public virtual ICollection<Tag> Tags { set; get; } // many-to-many

        public BlogPost()
        {
            Tags = new List<Tag>();
        }
    }

    public class Tag
    {
        public int Id { set; get; }

        [StringLength(maximumLength: 450), Required]
        public string Name { set; get; }

        public virtual ICollection<BlogPost> BlogPosts { set; get; } // many-to-many

        public Tag()
        {
            BlogPosts = new List<BlogPost>();
        }
    }

    public class MyContext : DbContext
    {
        public DbSet<BlogPost> BlogPosts { get; set; }
        public DbSet<Tag> Tags { get; set; }
    }

    public class Configuration : DbMigrationsConfiguration<MyContext>
    {
        public Configuration()
        {
            AutomaticMigrationsEnabled = true;
            AutomaticMigrationDataLossAllowed = true;
        }

        protected override void Seed(MyContext context)
        {
            var tag1 = new Tag { Name = "Tag1" };
            context.Tags.Add(tag1);

            var post1 = new BlogPost { Title = "Title...1", Body = "Body...1" };
            context.BlogPosts.Add(post1);

            post1.Tags.Add(tag1);

            base.Seed(context);
        }
    }

    public static class Test
    {
        public static void RunTests()
        {
            Database.SetInitializer(new MigrateDatabaseToLatestVersion<MyContext, Configuration>());

            using (var ctx = new MyContext())
            {
                var post1 = ctx.BlogPosts.Find(1);
                if (post1 != null)
                {
                    Console.WriteLine(post1.Title);
                }
            }
        }
    }
}

    public class TagMap : EntityTypeConfiguration<Tag>
    {
        public TagMap()
        {
            this.HasMany(x => x.BlogPosts)
                .WithMany(x => x.Tags)
                .Map(map =>
                    {
                        map.MapLeftKey("TagId");
                        map.MapRightKey("BlogPostId");
                        map.ToTable("BlogPostsJoinTags");
                    });
        }
    }

    public class MyContext : DbContext
    {
        public DbSet<BlogPost> BlogPosts { get; set; }
        public DbSet<Tag> Tags { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Configurations.Add(new TagMap());
            base.OnModelCreating(modelBuilder);
        }
    }

            using (var ctx = new MyContext())
            {
                var post1 = ctx.BlogPosts.Find(1);
                if (post1 != null)
                {
                    Console.WriteLine(post1.Title);
                    foreach (var tag in post1.Tags.ToList())
                        post1.Tags.Remove(tag);
                    ctx.SaveChanges();
                }
            }

                var post1 = ctx.BlogPosts.Find(1);
                if (post1 != null)
                {
                    ctx.BlogPosts.Remove(post1);
                    ctx.SaveChanges();
                }

                var post1 = ctx.BlogPosts.Find(1);
                if (post1 != null)
                {
                    var tag2 = new Tag { Name = "Tag2" };                    
                    post1.Tags.Add(tag2);
                    ctx.SaveChanges();
                }

                //نام تگ‌های دریافتی از کاربر  
                var tagsList = new[] { "Tag1", "Tag2", "Tag3" };

                //بارگذاری یک مطلب به همراه تگ‌های آن
                var post1 = ctx.BlogPosts.Include(x => x.Tags).FirstOrDefault(x => x.Id == 1);
                if (post1 != null)
                {
                    //ابتدا کلیه تگ‌های موجود را حذف خواهیم کرد
                    if (post1.Tags != null && post1.Tags.Any())
                        post1.Tags.Clear();

                    //سپس در طی فقط یک کوئری بررسی می‌کنیم کدامیک از موارد ارسالی موجود هستند
                    var listOfActualTags = ctx.Tags.Where(x => tagsList.Contains(x.Name)).ToList();
                    var listOfActualTagNames = listOfActualTags.Select(x => x.Name.ToLower()).ToList();

                    //فقط موارد جدید به تگ‌ها و ارتباطات موجود اضافه می‌شوند
                    foreach (var tag in tagsList)
                    {
                        if (!listOfActualTagNames.Contains(tag.ToLowerInvariant().Trim()))
                        {
                            ctx.Tags.Add(new Tag { Name = tag.Trim() });
                        }
                    }
                    ctx.SaveChanges(); // ثبت موارد جدید

                    //موارد قبلی هم حفظ می‌شوند
                    foreach (var item in listOfActualTags)
                    {
                        post1.Tags.Add(item);
                    }
                    ctx.SaveChanges();
                }

SELECT
[Extent1].[Id] AS [Id],
[Extent1].[Name] AS [Name]
FROM [dbo].[Tags] AS [Extent1]
WHERE [Extent1].[Name] IN (N'Tag1',N'Tag2',N'Tag3')

 ctx.BlogPosts.Where(p => p.Id == 1).Include(p => p.Tags).FirstOrDefault()

var posts = from p in ctx.BlogPosts
                 from t in p.Tags
                 where t.Name == "Tag1"
                 select p;

 var posts = ctx.Tags.Where(x => x.Name == "Tag1").SelectMany(x => x.BlogPosts);

    public class Place
    {
        public int Id { set; get; }
        public string Name { set; get; }

        public virtual ICollection<Person> Personnel { set; get; }
    }

    public class Person
    {
        public int Id { set; get; }
        public string FirstName { set; get; }
        public string LastName { set; get; }

        [ForeignKey("BirthPlaceId")]
        public virtual Place BirthPlace { set; get; }
        public int BirthPlaceId { set; get; }

        [ForeignKey("IssuanceLocationId")]
        public virtual Place IssuanceLocation { set; get; }
        public int? IssuanceLocationId { set; get; }
    }

var query = from personnel in context.Personnel
                            join issuanceLocation in context.Places on
                                  personnel.IssuanceLocationId equals issuanceLocation.Id into aIssuanceLocation
                            from IL in aIssuanceLocation.DefaultIfEmpty()
                            join birthLocation in context.Places on
                                  personnel.BirthPlaceId equals birthLocation.Id into aBirthLocation
                            from BL in aBirthLocation.DefaultIfEmpty()
                            select new
                               {
                                   personnel.Id,
                                   personnel.FirstName,
                                   personnel.LastName,
                                   IssuanceLocation = IL.Name,
                                   BirthLocation = BL.Name
                               };

SELECT
                        [Extent1].[Id] AS [Id],
                        [Extent1].[FirstName] AS [FirstName],
                        [Extent1].[LastName] AS [LastName],
                        [Extent2].[Name] AS [Name],
                        [Extent3].[Name] AS [Name1]
                        FROM [dbo].[People] AS [Extent1]
                        LEFT OUTER JOIN [dbo].[Places] AS [Extent2] ON [Extent1].[IssuanceLocationId] = [Extent2].[Id]
                        INNER JOIN [dbo].[Places] AS [Extent3] ON [Extent1].[BirthPlaceId] = [Extent3].[Id]

var query = context.Personnel.Select(x => new
             {
              x.Id,
              x.FirstName,
              x.LastName,
              BirthPlaceName = x.BirthPlace.Name,
              IssuanceLocationName = x.IssuanceLocation == null ? "" : x.IssuanceLocation.Name
             });

SELECT
    [Extent1].[Id] AS [Id],
    [Extent1].[FirstName] AS [FirstName],
    [Extent1].[LastName] AS [LastName],
    [Extent2].[Name] AS [Name],
    CASE WHEN ([Extent3].[Id] IS NULL) THEN N'' ELSE [Extent3].[Name] END AS [C1]
    FROM   [dbo].[People] AS [Extent1]
    INNER JOIN [dbo].[Places] AS [Extent2] ON [Extent1].[BirthPlaceId] = [Extent2].[Id]
    LEFT OUTER JOIN [dbo].[Places] AS [Extent3] ON [Extent1].[IssuanceLocationId] = [Extent3].[Id]

node -v

md \projects\node-edge-test1
cd \projects\node-edge-test1

npm install edge
npm install edge-sql

var edge = require('edge');

// The text in edge.func() is C# code
var helloWorld = edge.func('async (input) => { return input.ToString(); }');

helloWorld('Hello World!', function (error, result) {
    if (error) throw error;
    console.log(result);
});

node server.js

IF EXISTS(SELECT 1 FROM sys.tables WHERE object_id = OBJECT_ID('SampleUsers')) BEGIN; DROP TABLE SampleUsers; END; GO

CREATE TABLE SampleUsers ( Id INTEGER NOT NULL IDENTITY(1, 1), FirstName VARCHAR(255) NOT NULL, LastName VARCHAR(255) NOT NULL, Email VARCHAR(255) NOT NULL, CreateDate DATETIME NOT NULL DEFAULT(getdate()), PRIMARY KEY (Id) ); GO

INSERT INTO SampleUsers(FirstName,LastName,Email,CreateDate) VALUES('Orla','Sweeney','nunc@convallisincursus.ca','Apr 13, 2014');
INSERT INTO SampleUsers(FirstName,LastName,Email,CreateDate) VALUES('Zia','Pickett','porttitor.tellus.non@Duis.com','Aug 31, 2014');
INSERT INTO SampleUsers(FirstName,LastName,Email,CreateDate) VALUES('Justina','Ayala','neque.tellus.imperdiet@temporestac.com','Jul 28, 2014');
INSERT INTO SampleUsers(FirstName,LastName,Email,CreateDate) VALUES('Levi','Parrish','adipiscing.elit@velarcueu.com','Jun 21, 2014');
INSERT INTO SampleUsers(FirstName,LastName,Email,CreateDate) VALUES('Pearl','Warren','In@dignissimpharetra.org','Mar 3, 2014');

set EDGE_SQL_CONNECTION_STRING=Data Source=localhost;Initial Catalog=node-test;Integrated Security=True

SETX EDGE_SQL_CONNECTION_STRING "Data Source=localhost;Initial Catalog=node-test;Integrated Security=True"

var http = require('http');
var edge = require('edge');
var port = process.env.PORT || 8080;

var getTopUsers = edge.func('sql', function () {/*
    SELECT TOP 3 * FROM SampleUsers ORDER BY CreateDate DESC
*/});

function logError(err, res) {
    res.writeHead(200, { 'Content-Type': 'text/plain' });
    res.write("Error: " + err);
    res.end("");
}    

http.createServer(function (req, res) {
    res.writeHead(200, { 'Content-Type': 'text/html' });

    getTopUsers(null, function (error, result) {
        if (error) { logError(error, res); return; }
        if (result) {
            res.write("<ul>");
            result.forEach(function(user) {
                res.write("<li>" + user.FirstName + " " + user.LastName + ": " + user.Email + "</li>");
            });
            res.end("</ul>");
        }
        else {
        }
    });
}).listen(port);
console.log("Node server listening on port " + port);

node server-sql-query.js

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.Threading.Tasks;

namespace EdgeSampleLibrary
{
     public class Sample1
    {
        public async Task<object> Invoke(object input)
        {
            // Edge marshalls data to .NET using an IDictionary<string, object>
            var payload = (IDictionary<string, object>) input;
            var pageNumber = (int) payload["pageNumber"];
            var pageSize = (int) payload["pageSize"];
            return await QueryUsers(pageNumber, pageSize);
        }

        public async Task<List<SampleUser>> QueryUsers(int pageNumber, int pageSize)
        {
            // Use the same connection string env variable
            var connectionString = Environment.GetEnvironmentVariable("EDGE_SQL_CONNECTION_STRING");
            if (connectionString == null)
                throw new ArgumentException("You must set the EDGE_SQL_CONNECTION_STRING environment variable.");

            // Paging the result set using a common table expression (CTE).
            // You may rather do this in a stored procedure or use an 
            // ORM that supports async.
            var sql = @"
DECLARE @RowStart int, @RowEnd int;
SET @RowStart = (@PageNumber - 1) * @PageSize + 1;
SET @RowEnd = @PageNumber * @PageSize;

WITH Paging AS
(
    SELECT  ROW_NUMBER() OVER (ORDER BY CreateDate DESC) AS RowNum,
            Id, FirstName, LastName, Email, CreateDate
    FROM    SampleUsers
)
SELECT  Id, FirstName, LastName, Email, CreateDate
FROM    Paging
WHERE   RowNum BETWEEN @RowStart AND @RowEnd
ORDER BY RowNum;
";
            var users = new List<SampleUser>();

            using (var cnx = new SqlConnection(connectionString))
            {
                using (var cmd = new SqlCommand(sql, cnx))
                {
                    await cnx.OpenAsync();

                    cmd.Parameters.Add(new SqlParameter("@PageNumber", SqlDbType.Int) { Value = pageNumber });
                    cmd.Parameters.Add(new SqlParameter("@PageSize", SqlDbType.Int) { Value = pageSize });

                    using (var reader = await cmd.ExecuteReaderAsync(CommandBehavior.CloseConnection))
                    {
                        while (await reader.ReadAsync())
                        {
                            var user = new SampleUser
                            {
                                Id = reader.GetInt32(0), 
                                FirstName = reader.GetString(1), 
                                LastName = reader.GetString(2), 
                                Email = reader.GetString(3), 
                                CreateDate = reader.GetDateTime(4)
                            };
                           users.Add(user);
                        }
                    }
                }
            }
            return users;
        } 
    }

    public class SampleUser
    {
        public int Id { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string Email { get; set; }
        public DateTime CreateDate { get; set; }
    }
}

[project]/bin/Debug/EdgeSampleLibrary.dll

var http = require('http');
var edge = require('edge');
var port = process.env.PORT || 8080;

// Set up the assembly to call from Node.js 
var querySample = edge.func({ assemblyFile: 'EdgeSampleLibrary.dll', typeName: 'EdgeSampleLibrary.Sample1', methodName: 'Invoke' });

function logError(err, res) { res.writeHead(200, { 'Content-Type': 'text/plain' }); res.write("Got error: " + err); res.end(""); }

http.createServer(function (req, res) { res.writeHead(200, { 'Content-Type': 'text/html' });

    // This is the data we will pass to .NET
    var data = { pageNumber: 1, pageSize: 3 };

    // Invoke the .NET function
    querySample(data, function (error, result) {
        if (error) { logError(error, res); return; }
        if (result) {
            res.write("<ul>");
            result.forEach(function(user) {
                res.write("<li>" + user.FirstName + " " + user.LastName + ": " + user.Email + "</li>");
            });
            res.end("</ul>");
        }
        else {
            res.end("No results");
        }
    });

}).listen(port);

console.log("Node server listening on port " + port);

node server-dotnet-query.js

export interface IUser {
    id: number;
    name: string;
    email: string;
    password: string;
}

<form>
    <div class="form-group">
        <label form="name">Username</label>
        <input id="name" type="text" class="form-control" />
    </div>
    <div class="form-group">
        <label form="email">Email</label>
        <input id="email" type="text" class="form-control" />
    </div>
    <div class="form-group">
        <label form="password">Password</label>
        <input id="password" type="password" class="form-control" />
    </div>
    <button class="btn btn-primary" type="submit">Submit</button>
</form>

import { Component } from '@angular/core';
import { Control, ControlGroup, Validators } from '@angular/common';
 
@Component({
    selector: 'signup-form',
    templateUrl: 'app/users/signup-form.component.html'
})
export class SignupFormComponent {
    form = new ControlGroup({
        name: new Control('', Validators.required),
        email: new Control('', Validators.required),
        password: new Control('', Validators.required)
    });
 
    onSubmit(): void {
        console.log(this.form.value);
    }
}

<form [ngFormModel]="form" (ngSubmit)="onSubmit()">
    <div class="form-group">
        <label form="name">Username</label>
        <input id="name" type="text" class="form-control"
               ngControl="name"/>
        <label class="text-danger" *ngIf="!form.controls['name'].valid">
            Username is required.
        </label>
    </div>
    <div class="form-group">
        <label form="email">Email</label>
        <input id="email" type="text" class="form-control"
               ngControl="email" #email="ngForm"/>
        <label class="text-danger" *ngIf="email.touched && !email.valid">
            Email is required.
        </label>
    </div>
    <div class="form-group">
        <label form="password">Password</label>
        <input id="password" type="password" class="form-control"
               ngControl="password" #password="ngForm"/>
        <label class="text-danger" *ngIf="password.touched && !password.valid">
            Password is required.
        </label>
    </div>
    <button class="btn btn-primary" type="submit">Submit</button>
</form>

form = new ControlGroup({
    name: new Control('', Validators.required),
    email: new Control('', Validators.required),
    password: new Control('', Validators.required)
});

 import { Control, ControlGroup, Validators } from '@angular/common';

<form [ngFormModel]="form" (ngSubmit)="onSubmit()">

 <label class="text-danger" *ngIf="!form.controls['name'].valid">

    onSubmit(): void {
        console.log(this.form.value);
    }

//same as before...
import { SignupFormComponent } from './users/signup-form.component';
 
@Component({
    //same as before…
    template: `
                //same as before…                    
                <li><a [routerLink]="['AddUser']">Add User</a></li>
               //same as before…
    `,
    //same as before…
})
@RouteConfig([
    //same as before…    
    { path: '/adduser', name: 'AddUser', component: SignupFormComponent }
])
//same as before...

import { Control, ControlGroup, Validators, FormBuilder } from '@angular/common';

form: ControlGroup;
 
constructor(formBuilder: FormBuilder) {
    this.form = formBuilder.group({
        name: ['', Validators.required],
        email: ['', Validators.required],
        password: ['', Validators.required]
    });
}

import { Control } from '@angular/common';
 
export class UsernameValidators {
    static cannotContainSpace(control: Control) {
        if (control.value.indexOf(' ') >= 0) {
            return { cannotContainSpace: true };
        }
        return null;
    }
}

 { required:true }

{
  minlength : {
     requiredLength : 3,
     actualLength : 1
  }
}

 import { UsernameValidators } from './usernameValidators';

 name: ['', Validators.compose([Validators.required, UsernameValidators.cannotContainSpace])],

<div class="form-group">
    <label form="name">Username</label>
    <input id="name" type="text" class="form-control"
           ngControl="name"
           #name="ngForm" />
    <div *ngIf="name.touched && name.errors">
        <label class="text-danger" *ngIf="name.errors.required">
            Username is required.
        </label>
        <label class="text-danger" *ngIf="name.errors.cannotContainSpace">
            Username can't contain space.
        </label>
    </div>
</div>

import {Control} from '@angular/common';
 
export class EmailValidators {
    static email(control: Control) {
        var regEx = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
        var valid = regEx.test(control.value);
        return valid ? null : { email: true };
    }
}

 control(value: Object, validator?: ValidatorFn, asyncValidator?: AsyncValidatorFn) : Control

nameShouldBeUnique(control: Control) {
    let name: string = control.value;
    return new Promise((resolve) => {
        this._userService.isUserNameUnique(<IUser>{ "name": name }).subscribe(
            (result: IResult) => {
                resolve(                    
                    result.result ? null : { 'nameShouldBeUnique': true }
                );
            },
            error => {
                resolve(null);
            }
        );
    });
}

this.form = _formBuilder.group({
    name: ['', Validators.compose([
        Validators.required,
        UsernameValidators.cannotContainSpace
    ]),
        (control: Control) => this.nameShouldBeUnique(control)],

import { Injectable } from '@angular/core';
import { Http, Response } from '@angular/http';
import { Observable } from 'rxjs/Observable';
import { Headers, RequestOptions } from '@angular/http';
import { IUser } from  './user';
import { IResult } from './result';
 
@Injectable()
export class UserService {
    private _checkUserUrl = '/home/checkUser';
 
    constructor(private _http: Http) { }
 
    private handleError(error: Response) {
        console.error(error);
        return Observable.throw(error.json().error || 'Server error');
    }
 
    isUserNameUnique(user: IUser): Observable<IResult> {
        let headers = new Headers({ 'Content-Type': 'application/json' }); // for ASP.NET MVC
        let options = new RequestOptions({ headers: headers });
 
        return this._http.post(this._checkUserUrl, JSON.stringify(user), options)
            .map((response: Response) => <IResult>response.json())
            .do(data => console.log("User: " + JSON.stringify(data)))
            .catch(this.handleError);
    }
}

export interface IResult {
    result: boolean;
}

namespace MVC5Angular2.Controllers
{
    public class HomeController : Controller
    {
        [HttpPost]
        public ActionResult CheckUser(User user)
        {
            var isUnique = new { result = true };
            if (user.Name?.Equals("Vahid", StringComparison.OrdinalIgnoreCase) ?? false)
            {
                isUnique = new { result = false };
            }
 
            return new ContentResult
            {
                Content = JsonConvert.SerializeObject(isUnique, new JsonSerializerSettings
                {
                    ContractResolver = new CamelCasePropertyNamesContractResolver()
                }),
                ContentType = "application/json",
                ContentEncoding = Encoding.UTF8
            };
        }
    }
}

@Component({
    selector: 'signup-form',
    templateUrl: 'app/users/signup-form.component.html',
    providers: [ UserService ]
})
export class SignupFormComponent {
 
    constructor(private _formBuilder: FormBuilder, private _userService: UserService) {

<div *ngIf="name.touched && name.errors">
    <label class="text-danger" *ngIf="name.errors.required">
        Username is required.
    </label>
    <label class="text-danger" *ngIf="name.errors.cannotContainSpace">
        Username can't contain space.
    </label>
    <label class="text-danger" *ngIf="name.errors.nameShouldBeUnique">
        This username is already taken.
    </label>
</div>

<input id="name" type="text" class="form-control"
       ngControl="name"
       #name="ngForm" />
<div *ngIf="name.control.pending">
    Checking server, Please wait ...
</div>

onSubmit(): void {
    console.log(this.form.value);
 
    this.form.find('name').setErrors({
        invalidData : true
    }); 
}

<div *ngIf="name.touched && name.errors">
    <label class="text-danger" *ngIf="name.errors.invalidData">
        Check the inputs....
    </label>
</div>

  { name="VahidN", email="email@site.com", password="123"}

import { Injectable } from '@angular/core';
import { Http, Response } from '@angular/http';
import { Observable } from 'rxjs/Observable';
import { Headers, RequestOptions } from '@angular/http';
import { IUser } from  './user';
import { IResult } from './result';
 
@Injectable()
export class UserService {
    private _addUserUrl = '/home/addUser';
 
    constructor(private _http: Http) { }
 
    private handleError(error: Response) {
        console.error(error);
        return Observable.throw(error.json().error || 'Server error');
    }
 
    addUser(user: IUser): Observable<IUser> {
        let headers = new Headers({ 'Content-Type': 'application/json' }); // for ASP.NET MVC
        let options = new RequestOptions({ headers: headers });
 
        return this._http.post(this._addUserUrl, JSON.stringify(user), options)
            .map((response: Response) => <IUser>response.json())
            .do(data => console.log("User: " + JSON.stringify(data)))
            .catch(this.handleError);
    }
}

[HttpPost]
public ActionResult AddUser(User user)
{
    user.Id = 1; //todo: save user and get id from db
 
    return new ContentResult
    {
        Content = JsonConvert.SerializeObject(user, new JsonSerializerSettings
        {
            ContractResolver = new CamelCasePropertyNamesContractResolver()
        }),
        ContentType = "application/json",
        ContentEncoding = Encoding.UTF8
    };
}

onSubmit(): void {
    console.log(this.form.value);
 
    /*this.form.find('name').setErrors({
            invalidData : true
        });*/
 
    this._userService.addUser(<IUser>this.form.value)
        .subscribe((user: IUser) => {
            console.log(`ID: ${user.id}`);
        });
}

 Select * from sys.dm_os_buffer_descriptors

 select * from sys.dm_os_buffer_pool_extension_configuration

 ALTER SERVER CONFIGURATION
SET BUFFER POOL EXTENSION ON
 (FILENAME = 'd:\BufferPoolExt.BPE', SIZE = 1GB);

 ALTER SERVER CONFIGURATION
SET BUFFER POOL EXTENSION ON
 (FILENAME = 'd:\BufferPoolExt.BPE', SIZE = 10GB);

 Could not change the value of the 'BPoolExtensionPath' property

 ALTER SERVER CONFIGURATION
SET BUFFER POOL EXTENSION OFF

public static void CreateUniqueIndex(this DbContext context, string tableName, string fieldName)
{
      context.Database.ExecuteSqlCommand("CREATE UNIQUE INDEX [IX_Unique_" + tableName 
+ "_" + fieldName + "] ON [" + tableName + "]([" + fieldName + "] ASC);");
}

public class MyDbMigrationsConfiguration : DbMigrationsConfiguration<MyContext>
{
        public BlogDbMigrationsConfiguration()
        {
            AutomaticMigrationsEnabled = true;
            AutomaticMigrationDataLossAllowed = true;
        }

        protected override void Seed(MyContext context)
        {
            CreateUniqueIndex(context, "table1", "field1");
            base.Seed(context);
        }
}

using System;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using System.Data.Objects;
using System.Linq;
using System.Linq.Expressions;
using System.Text.RegularExpressions;

namespace General
{
    public static class ContextExtensions
    {
        public static string GetTableName<T>(this DbContext context) where T : class
        {
            ObjectContext objectContext = ((IObjectContextAdapter)context).ObjectContext;
            return objectContext.GetTableName<T>();
        }

        public static string GetTableName<T>(this ObjectContext context) where T : class
        {
            var sql = context.CreateObjectSet<T>().ToTraceString();
            var regex = new Regex("FROM (?<table>.*) AS");
            var match = regex.Match(sql);
            string table = match.Groups["table"].Value;
            return table
                    .Replace("`", string.Empty)
                    .Replace("[", string.Empty)
                    .Replace("]", string.Empty)
                    .Replace("dbo.", string.Empty)
                    .Trim();
        }

        private static bool hasUniqueIndex(this DbContext context, string tableName, string indexName)
        {
            var sql = "SELECT count(*) FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS where table_name = '" 
                      + tableName + "' and CONSTRAINT_NAME = '" + indexName + "'";
            var result = context.Database.SqlQuery<int>(sql).FirstOrDefault();
            return result > 0;
        }

        private static void createUniqueIndex(this DbContext context, string tableName, string fieldName)
        {
            var indexName = "IX_Unique_" + tableName + "_" + fieldName;
            if (hasUniqueIndex(context, tableName, indexName))
                return;

            var sql = "ALTER TABLE [" + tableName + "] ADD CONSTRAINT [" + indexName + "] UNIQUE ([" + fieldName + "])";
            context.Database.ExecuteSqlCommand(sql);
        }

        public static void CreateUniqueIndex<TEntity>(this DbContext context, Expression<Func<TEntity, object>> fieldName) where TEntity : class
        {
            var field = ((MemberExpression)fieldName.Body).Member.Name;
            createUniqueIndex(context, context.GetTableName<TEntity>(), field);
        }
    }
}

context.CreateUniqueIndex<User>(x=>x.Name);

public class UserViewModel
{
    public int Id { set; get; }
    public string CustomName { set; get; }
    public int PostsCount { set; get; }
}

public class TestProfile : Profile
{
    protected override void Configure()
    {
        this.CreateMap<User, UserViewModel>()
            .ForMember(dest => dest.CustomName,
                       opt => opt.MapFrom(src => src.Name + "[" + src.Age + "]"))
             .ForMember(dest => dest.PostsCount,
                        opt => opt.MapFrom(src => src.BlogPosts.Count()));
    }
 
    public override string ProfileName
    {
        get { return this.GetType().Name; }
    }
}

using (var context = new MyContext())
{
    var user1 = context.Users
                       .Project()
                       .To<UserViewModel>()
                       .FirstOrDefault();
 
    if (user1 != null)
    {
        Console.Write(user1.CustomName);
        Console.Write(user1.PostsCount);
    }
}

                SELECT
                    [Limit1].[Id] AS [Id],
                    [Limit1].[C1] AS [C1],
                    [Limit1].[C2] AS [C2]
                    FROM ( SELECT TOP (1)
                        [Project1].[Id] AS [Id],
                        CASE WHEN ([Project1].[Name] IS NULL) THEN N'' ELSE [Project1].[Name] END
                     + N'[' +  CAST( [Project1].[Age] AS nvarchar(max)) + N']' AS [C1],
                        [Project1].[C1] AS [C2]
                        FROM ( SELECT
                            [Extent1].[Id] AS [Id],
                            [Extent1].[Name] AS [Name],
                            [Extent1].[Age] AS [Age],
                            (SELECT
                                COUNT(1) AS [A1]
                                FROM [dbo].[BlogPosts] AS [Extent2]
                                WHERE [Extent1].[Id] = [Extent2].[UserId]) AS [C1]
                            FROM [dbo].[Users] AS [Extent1]
                        )  AS [Project1]
                    )  AS [Limit1]