<div class="btn-group" data-toggle="buttons-radio">
        <button class="btn" type="button">بلی</button>
        <button class="btn" type="button">خیر</button>
    </div>

using System.ComponentModel;
using System.ComponentModel.DataAnnotations;

namespace Mvc4TwitterBootStrapTest.Models
{
    public class User
    {
        public int Id { set; get; }

        [DisplayName("نام")]
        [Required(ErrorMessage="لطفا نام را تکمیل کنید")]
        public string Name { set; get; }

        [DisplayName("نام خانوادگی")]
        [Required(ErrorMessage = "لطفا نام خانوادگی را تکمیل کنید")]
        public string LastName { set; get; }

        [DisplayName("فعال است؟")]
        [UIHint("BootstrapBoolean")]
        public bool? IsActive { set; get; }
    }
}

@model bool?
@{  
    var yesIsSelected = Model.HasValue && Model.Value ? "active" : null;
    var noIsSelected = Model.HasValue && !Model.Value ? "active" : null;
    var isIndeterminate = !Model.HasValue ? "active" : null;
    var htmlField = ViewData.TemplateInfo.HtmlFieldPrefix;   
}
@Html.HiddenFor(model => model)
<div class="btn-group" data-toggle="buttons-radio">
    <button type="button" class="btn btn-info @yesIsSelected bool-@htmlField" onclick="$('#@htmlField').val(true);">
        بلی</button>
    <button type="button" class="btn btn-info @noIsSelected bool-@htmlField" onclick="$('#@htmlField').val(false);">
        خیر</button>
    @if (ViewData.ModelMetadata.IsNullableValueType)
    {
        <button type="button" class="btn btn-info @isIndeterminate bool-@htmlField" onclick="$('#@htmlField').val('');">
            نامشخص</button> 
    }
</div>

@model bool?
@if (Model.HasValue)
{
    if (Model.Value)
    {
    <span class="label label-success">بلی</span> 
    }
    else
    {
    <span class="label label-important">خیر</span> 
    }
}
else
{ 
    <span class="label label-inverse">نامشخص</span> 
}

 PM> Install-Package RefactorThis.GraphDiff

using System.Collections.Generic;
using System.ComponentModel.DataAnnotations.Schema;

namespace GraphDiffTests.Models
{
    public class BlogPost
    {
        public int Id { get; set; }
        public string Title { get; set; }
        public string Content { get; set; }

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

        [ForeignKey("UserId")]
        public virtual User User { get; set; }
        public int UserId { get; set; }

        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 User
    {
        public int Id { get; set; }
        public string Name { get; set; }

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

using System;
using System.Data.Entity;
using GraphDiffTests.Models;

namespace GraphDiffTests.Config
{
    public class MyContext : DbContext
    {
        public DbSet<User> Users { get; set; }
        public DbSet<BlogPost> BlogPosts { get; set; }
        public DbSet<Tag> Tags { get; set; }


        public MyContext()
            : base("Connection1")
        {
            this.Database.Log = sql => Console.Write(sql);
        }
    }
}

using System.Data.Entity.Migrations;
using System.Linq;
using GraphDiffTests.Models;

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

        protected override void Seed(MyContext context)
        {
            if(context.Users.Any())
                return;

            var user1 = new User {Name = "User 1"};
            context.Users.Add(user1);

            var tag1 = new Tag { Name = "Tag1" };
            context.Tags.Add(tag1);

            var post1 = new BlogPost { Title = "Title...1", Content = "Content...1", User = user1};
            context.BlogPosts.Add(post1);

            post1.Tags.Add(tag1);

            base.Seed(context);
        }
    }
}

            using (var context = new MyContext())
            {
                var user1 = new User { Id = 1, Name = "User 1_1_1" };
                var post1 = new BlogPost { Id = 1, Title = "Title...1_1", Content = "Body...1_1",
                    User = user1, UserId = user1.Id };
                var tags = new List<Tag>
                {
                    new Tag {Id = 1, Name = "Tag1_1"},
                    new Tag {Id=12, Name = "Tag2_1"},
                    new Tag {Name = "Tag3"},
                    new Tag {Name = "Tag4"},
                };
                tags.ForEach(tag => post1.Tags.Add(tag));

                context.UpdateGraph(post1, map => map
                    .OwnedEntity(p => p.User)
                    .OwnedCollection(p => p.Tags)
                    );

                context.SaveChanges();
            }

namespace ExplorerPCal.Hooks
{
    public class GetDateTimeFormatInjection : IEntryPoint
    {

        public GetDateTimeFormatInjection(RemoteHooking.IContext context, string channelName)
        {
            // connect to host...
            _interface = RemoteHooking.IpcConnectClient<MessagesReceiverInterface>(channelName);
            _interface.Ping();
        }

        public void Run(RemoteHooking.IContext context, string channelName)
        {
        }
    }
}

        public void Run(RemoteHooking.IContext context, string channelName)
        {
                GetDateFormatHook = LocalHook.Create(
                                        InTargetProc: LocalHook.GetProcAddress("kernel32.dll", "GetDateFormatW"),
                                        InNewProc: new GetDateFormatDelegate(getDateFormatInterceptor),
                                        InCallback: this);

        [DllImport("kernel32.dll", CallingConvention = CallingConvention.StdCall, CharSet = CharSet.Auto, SetLastError = true)]
        public static extern int GetDateFormatW(
                                        uint locale,
                                        uint dwFlags, // NLS_DATE_FLAGS
                                        SystemTime lpDate,
                                        [MarshalAs(UnmanagedType.LPWStr)] string lpFormat,
                                        StringBuilder lpDateStr,
                                        int sbSize);

        [UnmanagedFunctionPointer(CallingConvention.StdCall, CharSet = CharSet.Auto, SetLastError = true)]
        private delegate int GetDateFormatDelegate(
                                        uint locale,
                                        uint dwFlags,
                                        SystemTime lpDate,
                                        [MarshalAs(UnmanagedType.LPWStr)] string lpFormat,
                                        StringBuilder lpDateStr,
                                        int sbSize);

        private int getDateFormatInterceptor(
                                        uint locale,
                                        uint dwFlags,
                                        SystemTime lpDate,
                                        string lpFormat,
                                        StringBuilder lpDateStr,
                                        int sbSize)
        {

        }

public class MessagesReceiverInterface : MarshalByRefObject
{
    public void Ping()
    {
    }
}

 var channel = RemoteHooking.IpcCreateServer<MessagesReceiverInterface>(ref _channelName, WellKnownObjectMode.SingleCall);

 RemoteHooking.Inject(
  explorer.Id,
  InjectionOptions.Default | InjectionOptions.DoNotRequireStrongName,
  "ExplorerPCal.Hooks.dll", // 32-bit version (the same, because of using AnyCPU)
  "ExplorerPCal.Hooks.dll", // 64-bit version (the same, because of using AnyCPU)
  _channelName
);

 .ctor(IContext, %ArgumentList%)
void Run(IContext, %ArgumentList%)

             try
            {
                while (true)
                {
                    Thread.Sleep(500);
                    _interface.Ping();
                }
            }
            catch
            {
                _interface = null;
                // .NET Remoting will raise an exception if host is unreachable

            }

using System;
using System.Data.Entity;
using System.Data.Entity.Migrations;

namespace TestKeys
{
    public class Bill
    {
        public int Id { get; set; }
        public decimal Amount { set; get; }
        public virtual Account Account { get; set; }
    }

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

    public class MyContext : DbContext
    {
        public DbSet<Bill> Bills { get; set; }
        public DbSet<Account> Accounts { get; set; }
    }

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

        protected override void Seed(MyContext context)
        {
            var a1 = new Account { Name = "a1" };
            var a2 = new Account { Name = "a2" };

            var bill1 = new Bill { Amount = 100, Account = a1 };
            var bill2 = new Bill { Amount = 200, Account = a2 };

            context.Bills.Add(bill1);
            context.Bills.Add(bill2);
            base.Seed(context);
        }
    }

    public static class Test
    {
        public static void Start()
        {
            Database.SetInitializer(new MigrateDatabaseToLatestVersion<MyContext, Configuration>());
            using (var ctx = new MyContext())
            {
                var bill1 = ctx.Bills.Find(1);
                Console.WriteLine(bill1.Amount);
            }
        }
    }
}

using (var ctx = new MyContext())
{
     var bill1 = ctx.Bills.Find(1);
     var a2 = new Account { Id = 2, Name = "a2" };
     bill1.Account = a2;
     ctx.SaveChanges();
}

using (var ctx = new MyContext())
{
    var bill1 = ctx.Bills.Find(1);
    var a2 = ctx.Accounts.Find(2);
    bill1.Account = a2;
    ctx.SaveChanges();
}

public class Bill
{
        public int Id { get; set; }
        public decimal Amount { set; get; }

        [ForeignKey("AccountId")]
        public virtual Account Account { get; set; }
        public int AccountId { set; get; }
}

using (var ctx = new MyContext())
{
    var bill1 = ctx.Bills.Find(1);
    bill1.AccountId = 2;
    ctx.SaveChanges();
}

using (var ctx = new MyContext())
{
     var a2 = new Account { Id = 2, Name = "a2_a2" };
     ctx.Entry(a2).State = System.Data.EntityState.Modified;
     ctx.SaveChanges();
}

namespace ModelStateTest.Models
{
    public class User
    {
        public string Email { set; get; }
    }
}

using System.Web.Mvc;
using ModelStateTest.Models;

namespace ModelStateTest.Controllers
{
    public class HomeController : Controller
    {
        public ActionResult Index()
        {
            return View();
        }

        [HttpPost]
        public ActionResult Index(User model)
        {           
            model.Email = "?";
            return View(model);
        }
    }
}

@model ModelStateTest.Models.User

@{
    ViewBag.Title = "Index";
}

<h2>Index</h2>

@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)

    <fieldset>
        <legend>User</legend>

        <div class="editor-label">
            @Html.LabelFor(model => model.Email)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Email)
            @Html.ValidationMessageFor(model => model.Email)
        </div>

        <p>
            <input type="submit" value="Create" />
        </p>
    </fieldset>
}

 model.Email = "?";

 this.ModelState.Remove("Email");

 <input type="text" name="Email" id="Email" value="@Model.Email" />

public class Comment
{
    public int Id { get; set; }
    public string CommentText { get; set; }
    public string User { get; set; }
    
    public virtual ICollection<ArticleComment> ArticleComments { get; set; }
    public virtual ICollection<VideoComment> VideoComments { get; set; }
    public virtual ICollection<EventComment> EventComments { get; set; }
}

public class Article
{
    public Article()
    {
        ArticleComments = new HashSet<ArticleComment>();
    }
    
    public int Id { get; set; }
    public string Title { get; set; }
    public string Slug { get; set; }
    public string Description { get; set; }
    
    public virtual ICollection<ArticleComment> ArticleComments { get; set; }

}

public class Video
{
    public Video()
    {
        VideoComments = new HashSet<VideoComment>();
    }
    
    public int Id { get; set; }
    public string Url { get; set; }
    public string Description { get; set; }
    
    public virtual ICollection<VideoComment> VideoComments { get; set; }
}

public class Event
{
    public Event()
    {
        EventComments = new HashSet<EventComment>();
    }
    
    public int Id { get; set; }
    public string Name { get; set; }
    public DateTimeOffset? Start { get; set; }
    public DateTimeOffset? End { get; set; }
    
    public virtual ICollection<EventComment> EventComments { get; set; }
}

public class MyDbContext : DbContext
{
    public DbSet<Article> Articles { get; set; }
    public DbSet<ArticleComment> ArticleComments { get; set; }
    public DbSet<Video> Videos { get; set; }
    public DbSet<VideoComment> VideoComments { get; set; }
    public DbSet<Event> Events { get; set; }
    public DbSet<EventComment> EventComments { get; set; }
    public DbSet<Comment> Comments { get; set; }

    protected override void OnConfiguring(DbContextOptionsBuilder options)
        => options.UseSqlite("Data Source=polymorphic.db");

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<ArticleComment>(entity =>
        {
            entity.HasKey(e => new { e.CommentId, e.ArticleId })
                .HasName("PK_dbo.ArticleComments");

            entity.HasIndex(e => e.ArticleId)
                .HasName("IX_ArticleId");

            entity.HasIndex(e => e.CommentId)
                .HasName("IX_ArticleCommentId");

            entity.HasOne(d => d.Article)
                .WithMany(p => p.ArticleComments)
                .HasForeignKey(d => d.ArticleId)
                .HasConstraintName("FK_dbo.ArticleComments_dbo.Articles_ArticleId");

            entity.HasOne(d => d.Comment)
                .WithMany(p => p.ArticleComments)
                .HasForeignKey(d => d.CommentId)
                .HasConstraintName("FK_dbo.ArticleComments_dbo.Comments_CommentId");
        });
        
        modelBuilder.Entity<VideoComment>(entity =>
        {
            entity.HasKey(e => new { e.CommentId, e.VideoId })
                .HasName("PK_dbo.VideoComments");

            entity.HasIndex(e => e.VideoId)
                .HasName("IX_VideoId");

            entity.HasIndex(e => e.CommentId)
                .HasName("IX_VideoCommentId");

            entity.HasOne(d => d.Video)
                .WithMany(p => p.VideoComments)
                .HasForeignKey(d => d.VideoId)
                .HasConstraintName("FK_dbo.VideoComments_dbo.Videos_VideoId");

            entity.HasOne(d => d.Comment)
                .WithMany(p => p.VideoComments)
                .HasForeignKey(d => d.CommentId)
                .HasConstraintName("FK_dbo.VideoComments_dbo.Comments_CommentId");
        });
        
        modelBuilder.Entity<EventComment>(entity =>
        {
            entity.HasKey(e => new { e.CommentId, e.EventId })
                .HasName("PK_dbo.EventComments");

            entity.HasIndex(e => e.EventId)
                .HasName("IX_EventId");

            entity.HasIndex(e => e.CommentId)
                .HasName("IX_EventCommentId");

            entity.HasOne(d => d.Event)
                .WithMany(p => p.EventComments)
                .HasForeignKey(d => d.EventId)
                .HasConstraintName("FK_dbo.EventComments_dbo.Events_EventId");

            entity.HasOne(d => d.Comment)
                .WithMany(p => p.EventComments)
                .HasForeignKey(d => d.CommentId)
                .HasConstraintName("FK_dbo.EventComments_dbo.Comments_CommentId");
        });
    }
}

<script type=”text/javascript”>
 var person = new Object();
  person.firstname = “John”;
  person.lastname = “Doe”;
  person.age = 50;
  person.eyecolor = “blue”;
  document.write(person.firstname + “ is “ + person.age + “ years old.”);
</script>

result : John is 50 years old.

<script type=”text/javascript”>
var obj = {
   var1: “text1”,
   var2: 5,
   Method: function ()
   {
     alert(this.var1);
   }
  };
  obj.Method();
</script>

 Result : text1

 Obj.var3 = “text3”;

   var newobj = obj;
  newobj.var1 = "other text";
  alert(obj.var1);// other text
  alert(newobj.var1);// other text

 <script type=”text/javascript”>
  function Person(firstname, lastname, age, eyecolor)
  {
     this.firstname = firstname;
     this.lastname = lastname;
     this.age = age;
     this.eyecolor = eyecolor;
  }

   var myFather = new Person("John", "Doe", 50, "blue");
  document.write(myFather.firstname + " is " + myFather.age + " years old.");
  result : John is 50 years old.

   var myMother=new person("Sally","Rally",48,"green");
   document.write(myMother.firstname + " is " + myFather.age + " years old.");
   result : Sally is 48 years old.
  </script>

 var Person = function (firstname, lastname, age, eyecolor)
  {
     this.firstname = firstname;
     this.lastname = lastname;
     this.age = age;
     this.eyecolor = eyecolor;
  }

  var myFather = new Person("John", "Doe", 50, "blue");
  document.write(myFather.firstname + " is " + myFather.age + " years old.");
   result : John is 50 years old.

   var myMother=new person("Sally","Rally",48,"green");
   document.write(myMother.firstname + " is " + myFather.age + " years old.");
   result : Sally is 48 years old.

<script type="text/javascript">
   function cat(name) {
      this.name = name;
      this.talk = function() {
      alert( this.name + " say meeow!" )
   }
 }

cat1 = new cat("felix")
cat1.talk() //alerts "felix says meeow!"
cat2 = new cat("ginger")
cat2.talk() //alerts "ginger says meeow!"
</Script>

 var myObjectLiteral = {
    property1: "one",
    property2: "two",
    method1: function() {
       alert("Hello world!");
}}
var myChild = Object.create(myObjectLiteral);
myChild.method1(); // will alert "Hello world!"

 function User (theName, theEmail) {
    this.name = theName;
    this.email = theEmail;
    this.quizScores = [];
    this.currentScore = 0;
}

 User.prototype = {
  saveScore:function (theScoreToAdd)  {
   this.quizScores.push(theScoreToAdd)
  },
  showNameAndScores:function ()  {
    var scores = this.quizScores.length > 0 ? this.quizScores.join(",") : "No Scores Yet";
    return this.name + " Scores: " + scores;
  },
  changeEmail:function (newEmail)  {
    this.email = newEmail;
    return "New Email Saved: " + this.email;
  }
}

 // A User
  firstUser = new User("Richard", "Richard@examnple.com");
  firstUser.changeEmail("RichardB@examnple.com");
  firstUser.saveScore(15);
  firstUser.saveScore(10);
  document.write(firstUser.showNameAndScores()); //Richard Scores: 15,10
  document.write('<br/>');
  // Another User
  secondUser = new User("Peter", "Peter@examnple.com");
  secondUser.saveScore(18);
  document.write(secondUser.showNameAndScores()); //Peter Scores: 18

 <script type="text/javascript">
function Base()
  {
     this.color = "blue";
  }
  function Sub()
  {
  }
  Sub.prototype = new Base();
  Sub.prototype.showColor = function ()
  {
     alert(this.color);
  }
  var instance = new Sub();
  instance.showColor(); //"blue"
</Script>

 <script language="javascript" type="text/javascript">
if (typeof Object.create !== 'function') {
Object.create = function (o) {
ایجاد یک کلاس خالی که قرار است خواص کلاس دریافتی توسط آرگومان کلاس پایه را به ارث ببرد//
  function F() {
}
با ارث برده شود F  باعث میشویم کلیه خواص و متدهای دریافتی توسط Prototype  توسط خصوصیت  F با انتساب آرگومان دریافتی که یک شی است به کلاس
  F.prototype = o;
   return new F(); 
  };
}

var cars = {
type: "sedan",
wheels: 4
  };
  // We want to inherit from the cars object, so we do:
  var toyota = Object.create(cars);
// now toyota inherits the properties from cars
  document.write(toyota.type);
</script>
output :sedan

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}`);
        });
}