How to validate a date using 3 dropdowns( day, month, year ) using jquery unobtrusive validation?
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I have a model to validate and the problem is the date of birth field.
It must be composed of 3 dropdowns (day, month, year).

    <div id="dob-editor-field" class="model-field-editor">
          @Html.LabelFor(m => m.DateOfBirth, new { @class = "label-div" })
          @Html.Telerik().DropDownList().Name("DobDay").BindTo((SelectList)ViewData["Days"]).HtmlAttributes(new {id = "DobDaySel"})
          @Html.Telerik().DropDownList().Name("DobMonth").BindTo((SelectList)ViewData["Months"]).HtmlAttributes(new { id = "DobMonthSel"})
          @Html.Telerik().DropDownList().Name("DobYear").BindTo((SelectList)ViewData["Years"]).HtmlAttributes(new { id = "DobYearSel" })
          @Html.ValidationMessageFor(m => m.DateOfBirth)
    </div>

On the server side i do this

            [HttpPost]
            public ActionResult Register(RegistrationModel regInfo, int DobDay, int DobMonth, int DobYear)
            {
                SetRegisterViewData(DobDay, DobMonth, DobYear);
                if (DobDay == 0 || DobMonth == 0 && DobYear == 0)
                {
                    ModelState.AddModelError("DateOfBirth", "Date of birth is required");
                }
                else
                {
                    DateTime dt = new DateTime(DobYear, DobMonth, DobDay);
                    long ticks = DateTime.Now.Ticks - dt.Ticks;
                    int years = new DateTime(ticks).Year;
                    if (years < 18)
                    {
                        ModelState.AddModelError("DateOfBirth", "You must be at least 18");
                    }
                }            
                if (ModelState.IsValid)
                {
                    //register user
                    return RedirectToAction("Index", "Home");
                }
                return View(regInfo);
            }

Questions:

 1. Server side : how to make it better? (i am thinking of adding dob,
    month, and year properties RegistrationModel and add attribute on
    DateOfBirth to check those properties)
 2. Client side : i was looking at http://stackoverflow.com/questions/4747184/perform-client-side-validation-for-custom-attribute but it got me confused.  What is the way to make it?
