In this article I will explain with an example, how to perform Password and Confirm Password validation on Server Side using Data Annotation attribute in ASP.Net MVC Razor.
The Data Annotation attributes will be applied to the Model class properties in ASP.Net MVC Razor.
The following Model class consists of two properties Password and ConfirmPassword. The properties are decorated with the following Data Annotation attributes for performing validations.
1. Required Data Annotation attribute.
2. Compare Data Annotation attribute. In this case Password.
Note: The Data Annotations attributes can be used with the Entity Data Model (EDM), LINQ to SQL, and other data models.
The Required Data Annotation and the Compare Data Annotation attributes have been specified with a property Error Message with a string value. As the name suggests, this string value will be displayed to the user when the respective validation fails.
The first parameter of the Compare attribute has been set with the name of the property with which the value needs to be compared i.e. Password.
using System.ComponentModel.DataAnnotations;
namespace Compare_Password_Validation_ServerSide_MVC.Models
    public class PersonModel
        [Required(ErrorMessage = "Password is required.")]
        public string Password { get; set; }
        [Required(ErrorMessage = "Confirmation Password is required.")]
        [Compare("Password", ErrorMessage = "Password and Confirmation Password must match.")]
        public string ConfirmPassword { get; set; }
The Controller consists of following two Action methods.
Action method for handling GET operation
Inside this Action method, simply the View is returned.
Action method for handling POST operation
This Action method handles the POST operation and when the form is submitted, the object of the PersonModel class is sent to this method.
The state of the submitted Model is checked using ModelState.IsValid property.
Note: ModelState.IsValid property is an inbuilt property which verifies two things:
1. Whether the Form values are bound to the Model.
2. All the validations specified inside Model class using Data annotations have been passed.
public class HomeController : Controller
    // GET: Home
    public ActionResult Index()
        return View();
    public ActionResult Index(PersonModel person)
        if (ModelState.IsValid)
            // Validation success.
        return View();
Inside the View, in the very first line the PersonModel class is declared as Model for the View.
The Form
The View consists of an HTML Form which has been created using the Html.BeginForm method with the following parameters.
ActionName – Name of the Action. In this case the name is Index.
ControllerName – Name of the Controller. In this case the name is Home.
FormMethod – It specifies the Form Method i.e. GET or POST. In this case it will be set to POST.
Implementing Validation
The Form consists of the following HTML Helper functions:-
1. Html.TextBoxFor – Creating a Password TextBox for the Model property.
The Html.TextBoxFor has been assigned with htmlAttributes type as password.
2. Html.ValidationMessageFor – Displaying the Validation message for the property.
There is also Submit button which when clicked, the Form gets submitted and the Model is sent to the Controller.
@model Compare_Password_Validation_ServerSide_MVC.Models.PersonModel
    Layout = null;
<!DOCTYPE html>
    <meta name="viewport" content="width=device-width" />
    <style type="text/css">
        body { font-family: Arial; font-size: 10pt; }
        .error { color: red; }
    @using (Html.BeginForm("Index", "Home", FormMethod.Post))
                <td>@Html.TextBoxFor(m => m.Password, new { type = "password" })</td>
                <td>@Html.ValidationMessageFor(m => m.Password, "", new { @class = "error" })</td>
                <td>Confirm Password</td>
                <td>@Html.TextBoxFor(m => m.ConfirmPassword, new { type = "password" })</td>
                <td>@Html.ValidationMessageFor(m => m.ConfirmPassword, "", new { @class = "error" })</td>
                <td><input type="submit" value="Submit" /></td>
ASP.Net MVC: Server Side Password and Confirm Password validation using Data Annotations