Email model validation with DataAnnotations and DataType In ASP.NET MVC

In ASP.NET MVC, you can perform model validation using DataAnnotations and the DataType attribute to ensure that the data entered by users adheres to the expected format and constraints. This helps maintain data integrity and improve the user experience. Here's a step-by-step guide on how to do this:

1. Create a Model: Start by creating a model class that represents the data you want to validate. This can be done in the Models folder of your MVC project.

   using System;
   using System.ComponentModel.DataAnnotations;
   
   public class EmailModel
   {
       [Required(ErrorMessage = "Email address is required.")]
       [DataType(DataType.EmailAddress)]
       [EmailAddress(ErrorMessage = "Invalid email address.")]
       public string Email { get; set; }
   }
   

   In the above example, we have created an EmailModel class with an Email property that should be a valid email address. We've used the Required, DataType, and EmailAddress attributes for validation.

2. Controller Action: In your controller, create an action method that will handle the form submission and validate the EmailModel.

   using System.Web.Mvc;
   
   public class EmailController : Controller
   {
       public ActionResult Index()
       {
           return View();
       }
   
       [HttpPost]
       public ActionResult SendEmail(EmailModel model)
       {
           if (ModelState.IsValid)
           {
               // The model is valid, so process the email and send it.
               // You can access the validated email address using model.Email.
               // Perform your email sending logic here.
               return RedirectToAction("Success");
           }
   
           // If the model is not valid, return to the form with validation errors.
           return View("Index", model);
       }
   
       public ActionResult Success()
       {
           return View();
       }
   }
   

   In the SendEmail action, we check if the ModelState is valid. If it is, the email is processed and sent. If not, the user is redirected back to the form with validation errors.

3. Create Views: Create the views for your controller actions, including the form for submitting the email and the success page.

   • Create a view for the Index action, which will render the form for submitting the email.

   @model EmailModel
   @using (Html.BeginForm("SendEmail", "Email", FormMethod.Post))
   {
       @Html.LabelFor(model => model.Email)
       @Html.TextBoxFor(model => model.Email)
       @Html.ValidationMessageFor(model => model.Email)
       <input type="submit" value="Send Email" />
   }
   

   • Create a view for the Success action to display a success message.

   <h2>Email Sent Successfully</h2>
   

4. Configure Validation Summary: You can add a validation summary to your form to display a list of validation errors. You can add the following line to your Index view to display a summary of validation errors:

   @Html.ValidationSummary()
   

5. Client-Side Validation: By default, ASP.NET MVC provides client-side validation for DataAnnotations. Ensure that you include the necessary JavaScript libraries, like jQuery Validate, to enable client-side validation. You can do this by including the following in your layout view:

   @Scripts.Render("~/bundles/jquery")
   @Scripts.Render("~/bundles/jqueryval")
   

Now, when a user submits the form, the EmailModel will be validated, and if the email address is not in the correct format or is missing, the user will be shown validation error messages. If the model is valid, the email will be sent, and the user will be redirected to the success page.