ASP.NET MVC Registration form with Validation

 public class RegistrationModel
 {
 [Required(ErrorMessage = "Please Enter Email Address")]
 [Display(Name = "UserName")]
 [RegularExpression(".+@.+\\..+", ErrorMessage = "Please Enter Correct Email Address")]
 public string UserName { get; set; }
 
 [Required(ErrorMessage = "Please Enter Password")]
 [StringLength(50, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 6)]
 [DataType(DataType.Password)]
 [Display(Name = "Password")]
 public string Password { get; set; }
 
 [Required(ErrorMessage = "Please Enter Confirm Password")]
 [StringLength(50, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 6)]
 [DataType(DataType.Password)]
 [Display(Name = "Confirm password")]
 [Compare("Password", ErrorMessage = "The password and confirmation password do not match.")]
 public string ConfirmPassword { get; set; }
 
 [Display(Name = "Country")]
 public Country Country { get; set; }
 
 [Display(Name = "City")]
 public City City { get; set; }
 
 [Required(ErrorMessage = "Please Enter Address")]
 [Display(Name = "Address")]
 [StringLength(200)]
 public string Address { get; set; }
 
 [Required(ErrorMessage = "Please Enter Mobile No")]
 [Display(Name = "Mobile")]
 [StringLength(10, ErrorMessage = "The Mobile must contains 10 characters", MinimumLength = 10)]
 public string MobileNo { get; set; }
 
 [MustBeTrue(ErrorMessage = "Please Accept the Terms & Conditions")]
 public bool TermsAccepted { get; set; }
}

public class MustBeTrueAttribute : ValidationAttribute, IClientValidatable // IClientValidatable for client side Validation
{
 public override bool IsValid(object value)
 {
 return value is bool && (bool)value;
 }
 // Implement IClientValidatable for client side Validation
 public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
 {
 return new ModelClientValidationRule[] { new ModelClientValidationRule { ValidationType = "checkbox", ErrorMessage = this.ErrorMessage } };
 }
}

public class MustBeSelected : ValidationAttribute, IClientValidatable // IClientValidatable for client side Validation
{
 public override bool IsValid(object value)
 {
 if (value == null || (int)value == 0)
 return false;
 else
 return true;
 }
 // Implement IClientValidatable for client side Validation
 public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
 {
 return new ModelClientValidationRule[] { new ModelClientValidationRule { ValidationType = "dropdown", ErrorMessage = this.ErrorMessage } };
 }
}

public class Country
{
 [MustBeSelected(ErrorMessage = "Please Select Country")]
 public int? ID { get; set; }
 public string Name { get; set; }
}

public class City
{
 [MustBeSelected(ErrorMessage = "Please Select City")]
 public int? ID { get; set; }
 public string Name { get; set; }
 public int? Country { get; set; }
}

}
  

@model Mvc4_RegistrationForm.Models.RegistrationModel
<script type="text/jscript">
jQuery.validator.unobtrusive.adapters.add("dropdown", function (options) {
 if (options.element.tagName.toUpperCase() == "SELECT" && options.element.type.toUpperCase() == "SELECT-ONE") {
 options.rules["required"] = true;
 if (options.message) {
 options.messages["required"] = options.message;
 }
 }
});

jQuery.validator.unobtrusive.adapters.add("checkbox", function (options) {
 if (options.element.tagName.toUpperCase() == "INPUT" && options.element.type.toUpperCase() == "CHECKBOX") {
 options.rules["required"] = true;
 if (options.message) {
 options.messages["required"] = options.message;
 }
 }
});

$(function () {
 $('#Country_ID').change(function () {
 var id = $("#Country_ID :selected").val();
 if (id != "") {
 $.ajax({
 type: "GET",
 contentType: "application/json; charset=utf-8",
 url: '@Url.Action("CityList", "Home")',
 data: { "mCountry": id },
 dataType: "json"
 success: function (data) {
 var items = "";
 $.each(data, function (i, city) {
 items += "<option value='" + city.Value + "'>" + city.Text + "</option>";
 });
 $('#City_ID').html(items);
 },
 error: function (result) {
 alert('Service call failed: ' + result.status + ' Type :' + result.statusText);
 }
 });
 }
 else {
 var items = '<option value="">Select</option>';
 $('#City_ID').html(items);
 }
 });

});

</script>
 
@using (Html.BeginForm())
{
lt;fieldset>
 <legend></legend>
 <ol>
 <li>
 @Html.LabelFor(m => m.UserName)
 @Html.TextBoxFor(m => m.UserName, new { maxlength = 50 })
 @Html.ValidationMessageFor(m => m.UserName)
 </li>
 <li>
 @Html.LabelFor(m => m.Password)
 @Html.PasswordFor(m => m.Password, new { maxlength = 50, value = ViewBag.Selpwd })
 @Html.ValidationMessageFor(m => m.Password)
 </li>
 <li>
 @Html.LabelFor(m => m.ConfirmPassword)
 @Html.PasswordFor(m => m.ConfirmPassword, new { maxlength = 50, value = ViewBag.Selconfirmpwd })
 @Html.ValidationMessageFor(m => m.ConfirmPassword)
 </li>
 <li>
 @Html.LabelFor(m => m.Country)
 @Html.DropDownListFor(m => m.Country.ID, new SelectList(ViewBag.Country, "ID", "Name", ViewBag.SelCountry), new { style = "width:310px" })
 @Html.ValidationMessageFor(m => m.Country.ID)
 </li>
 lt;li>
 @Html.LabelFor(m => m.City)
 @Html.DropDownListFor(m => m.City.ID, new SelectList(ViewBag.City, "ID", "Name", ViewBag.SelCity), new { style = "width:310px" })
 @Html.ValidationMessageFor(m => m.City.ID)
 </li>
 <li>
 @Html.LabelFor(m => m.Address)
 @Html.TextAreaFor(m => m.Address, new { maxlength =200 })
 @Html.ValidationMessageFor(m => m.Address)
 </li>
 <li>
 @Html.LabelFor(m => m.MobileNo)
 @Html.TextBoxFor(m => m.MobileNo ,new { maxlength = 10 })
 @Html.ValidationMessageFor(m => m.MobileNo)
 </li>
 <li>
 @Html.CheckBoxFor(m => m.TermsAccepted) I accept the terms & conditions
 @Html.ValidationMessageFor(m => m.TermsAccepted)
 </li>
 </ol>
 <input type="submit" value="Submit" />
</fieldset>
}
 

public ActionResult RegistrationForm()
{
 BindCountry();
 BindCity(0);
 return View();
}

[HttpPost]
public ActionResult RegistrationForm(RegistrationModel mRegister)
{
 //This will check Server Side Validation by using data annotation
 if (ModelState.IsValid)
 {
 return View("Completed");
 }
 else
 {
 // To DO: if client validation failed
 ViewBag.Selpwd = mRegister.Password; //for setting password value
 ViewBag.Selconfirmpwd = mRegister.ConfirmPassword;
 ViewBag.SelCountry = mRegister.Country; // for setting selected country
 BindCountry();
 ViewBag.SelCity = mRegister.City;// for setting selected city
 
 if (mRegister.Country != null)
 BindCity(mRegister.Country.ID);
 else
 BindCity(null);
 
 return View();
 }
}