How to validate strong password in asp.net MVC

In this article I am going to explain how to validate strong password in asp.net MVC. 

Description:

Password ensure the security for confidential information/data which is stored on your system or online anywhere. If you use weak password, it allow hackers to get access easily. So we have to always force users to set strong password. In strong password user must one uppercase, one lowercase, one special and one numeric (number) character.

Implementations:

I am going to create users for application.

Model

Add Dataannotations namespace to login class.

    using System;

    using System.Collections.Generic;

    using System.ComponentModel.DataAnnotations;

    public partial class Login

    {

        public int Id { get; set; }

        [Required (ErrorMessage="Please enter username")]

        public string Username { get; set; }

         [Required(ErrorMessage = "Please enter password")]

         [DataType(DataType.Password)]

         [StringLength(100, ErrorMessage = "Password \"{0}\" must have {2} character", MinimumLength = 8)]

         [RegularExpression(@"^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[$@$!%*?&])[A-Za-z\d$@$!%*?&]{6,}$", ErrorMessage = "Password must contain: Minimum 8 characters atleast 1 UpperCase Alphabet, 1 LowerCase Alphabet, 1 Number and 1 Special Character")]

        public string Password { get; set; }

          [Display(Name = "Confirm password")]

         [Required(ErrorMessage = "Please enter confirm password")]

         [Compare("Password", ErrorMessage = "Confirm password doesn't match, Type again !")]

         [DataType(DataType.Password)]

        public string Confirmpwd { get; set; }

        public Nullable<bool> Is_Deleted { get; set; }

    }

Add Controller

Add an empty controller to project. Create an action createuser to add users for application.

Complete code of controller

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.Mvc;

using mvctest2017.Models;

using System.Security.Cryptography;

namespace mvctest2017.Controllers

{

  

    public class LoginController : Controller

    {

        //

        // GET: /Login/

        DemoEntities db = new DemoEntities();

        public ActionResult Index()

        {

            return View();

        }

        [HttpPost]

        public ActionResult Createuser()

        {           

            return View();

        }

        [HttpPost]

        public ActionResult Createuser(Login objlogin)

        {

            if (ModelState.IsValid)

            {

                db.Logins.Add(objlogin);

                db.SaveChanges();

            }

            return View();

        }

    }

}

Add View

Add view for createuser action.

Complete source of View

@model mvctest2017.Models.Login

@{

    ViewBag.Title = "Create user";

}

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>

<script src="~/Scripts/passwordscheck.js"></script>

<link href="~/Scripts/passwordscheck.css" rel="stylesheet" />

<h2>Create user</h2>

@using (Html.BeginForm()) {

    @*@Html.AntiForgeryToken()*@

    @Html.ValidationSummary(true)

    <fieldset id="register">

        <legend>Create user</legend>

        <div class="editor-label">

            @Html.LabelFor(model => model.Username)

        </div>

        <div class="editor-field">

            @Html.EditorFor(model => model.Username)

            @Html.ValidationMessageFor(model => model.Username)

        </div>

        <div class="editor-label">

            @Html.LabelFor(model => model.Password)

        </div>

        <div class="editor-field">

            @Html.PasswordFor(model => model.Password, new { id = "password" })

           <span id="result"></span>

            @Html.ValidationMessageFor(model => model.Password)

        </div>

        <div class="editor-label">

            @Html.LabelFor(model => model.Confirmpwd)

        </div>

        <div class="editor-field">

            @Html.PasswordFor(model => model.Confirmpwd)

            @Html.ValidationMessageFor(model => model.Confirmpwd)

        </div>

        <p>

            <input type="submit" value="Create" />

        </p>

    </fieldset>

}

<script src="~/Scripts/jquery.validate.min.js"></script>

<script src="~/Scripts/jquery.validate.unobtrusive.min.js"></script>