Creating a DropDownList with Validation in MVC

Question

_{Thursday, March 12, 2015 4:58 AM}

Hi,

Im new to MVC, my aim is to create a dropdownlist, with model validation.

I have a database with multiple columns i was to display only one unique value from that column and not multiple of the same one. 

e.g. column "age" the data could be 21, 24, 21, 22, 21

I would only like to show 21 once in the dropdownlist.

This is what i have done so far

Controller 

public ActionResult Index(string age)
{

var AgeLst = new List<string>();
var AgeQry = from r in db.table1
orderby r.age
select r.age;
AgeLst.AddRange(AgeQry.Distinct());
ViewBag.age = new SelectList(AgeLst);

}

View

<p>Age: @Html.DropDownList("age")</p>

I want to add some validation to the dropdownlist to make it a required field, im not sure if what ive shown above is best practice but I have used a Model view before to allow validation but not sure how to go about this.

Hope what i have posted is clear but if you need more information please let me know. 

How do i add a Model so i can add in - [required]

All replies (3)

_{Monday, March 16, 2015 1:46 AM ✅Answered}

Hi

Thanks for your post.

Please refer to the following code:

View Model:

public class ViewModel
{
    [Required]
    public int SelectedOptionID { get; set; }
}

View:

@model ViewModel

@using (Html.BeginForm())
{
    

    @Html.DropDownListFor(m => m.SelectedOptionID,
        ViewBag.age as SelectList,
        "Select an option")
    @Html.ValidationMessageFor(Model => Model.SelectedOptionID)
}

Hope this can be helpful to you.

Sherwin Zhao
Best Regards

---

_{Thursday, March 12, 2015 5:17 AM}

for dropdown validation refer this link:

http://stackoverflow.com/questions/19299459/validation-for-dropdown-list-in-mvc

---

_{Thursday, March 12, 2015 6:52 AM}

Hi 

Please visit this page for your solution..

http://www.nextprogramming.com/Tutorials/mvc/bind-dropdownlist-in-asp-net-mvc-3-razor-with-validation

Hope this will help you. Mark as answer if help it.

Thanks