Loading dropdownlist in entity framework

Question

0.00/5 (No votes)

See more:

Hello, I am new to Entity Framework with MVC
I created my model classes Faculty and Department.

C#

public class Faculty
  {
      [Key]
      public int FacultyID { get; set; }

      [Required(ErrorMessage = "Enter Faculty Name")]
      [Display(Name = "Faculty Name")]
      public string FacultyName { get; set; }

      public virtual ICollection<Department> Departments { get; set; }
  }

C#

public class Department
   {
       [Key]
       public int Id { get; set; }

       //[Required(ErrorMessage ="Enter Department ID")]
       //[Display(Name ="Department ID")]
       //public string departmentID { get; set; }

       [Required(ErrorMessage = "Enter Department Name")]
       [Display(Name = "Department Name")]
       public string DepartmentName { get; set; }

       public virtual Faculty Faculty { get; set; }


       [Required(ErrorMessage = "Select Faculty")]
       [Display(Name = "Faculty")]
       public int FacultyID { get; set; }
   }

So i generated a view for the two models
The field for faculty id in create department looks like this.

<div class="form-group">
            @Html.LabelFor(model => model.FacultyID, "FacultyID", htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.DropDownList("FacultyID", null, htmlAttributes: new { @class = "form-control" })
                @Html.ValidationMessageFor(model => model.FacultyID, "", new { @class = "text-danger" })
            </div>
        </div>

So how do i use the viewbag to display the list of faculties in the dropdownlist in the view? Thanks

What I have tried:

I tried to use Viewbag in the Department Create action

C#

public ActionResult Create()
        {
            ViewBag.FacultyID = new SelectList(db.Faculties, "FacultyID", "FacultyName");
            return View();
        }

Posted 26-Aug-16 2:58am

Adewagold

Updated 27-Aug-16 1:32am

Add a Solution

2 solutions

Solution 2

Quote:
Rightly directed by David_Wimbley, creating strongly typed view is good to go for...

In case interested in using strongly typed view follow 3 steps as below;
1. create a viewmodel that will hold Department and Faculty list

C#

public class DepartmentViewModel
    {
        public Department Department { get; set; }
        public List<Faculty> Faculty { get; set; }
    }

2. Controller will be

C#

public ActionResult Create()
        {
            //assuming faculty list is created somewhere else
            var DepartmentViewModel = new DepartmentViewModel { Faculty=faculties};
            return View(DepartmentViewModel);
        }

3. and view will be (if needed this dropdown list can also be created as partial view)

@model DropDownListDemo.Models.DepartmentViewModel

@using (Html.BeginForm())
{
    @Html.AntiForgeryToken()

    <div class="form-horizontal">
        @Html.DropDownListFor(model => model.Department.FacultyID, new SelectList(Model.Faculty, "FacultyID", "FacultyName"));
    </div>
}

Posted 27-Aug-16 1:32am

Maheshbhushan_Kshirsagar

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

David_Wimbley · Accepted Answer · 2016-08-26T03:56:00

I would recommend passing this via model. Also, I don't think you can use SelectList in MVC for DropDownListFor, i think you have to use a List of SelectListItem (or IEnumerable).

So the syntax for DropDownListFor can be something as simple as this

C#

@Html.DropDownListFor(m=>m.Name, new List<SelectListItem>(), new{@class="form-control"})

m=>m.Name is the property name for your model and new List<selectlistitem> is your collection of items to display in the drop down. But notice, if you are not using a model in your view, you can't use DropDownListFor, instead, simply DropDownList will work as it is not strongly typed.

C#

@Html.DropDownList("Name", new List<SelectListItem>(), new{@class="form-control"})

A more working example would be something similar to the following

Controller Action

C#

public ActionResult Index()
        {
            var list = new List<People>();
            list.Add(new People { Name = "David" });
            list.Add(new People { Name = "Thom" });

            var selectList = new List<SelectListItem>();

            foreach (var item in list)
            {
                selectList.Add(new SelectListItem { Text = item.Name, Value = item.Name});
            }

            return View(selectList);
        }

View - Index.cshtml

HTML

@model IEnumerable<SelectListItem>

@{
    ViewBag.Title = "Home Page";
}


@Html.DropDownList("Name", Model, new{@class="form-control"})

But to use viewbag, you would do the same thing, but instead of model you just do

Controller

C#

public ActionResult Index()
        {
            var list = new List<People>();
            list.Add(new People { Name = "David" });
            list.Add(new People { Name = "Thom" });

            var selectList = new List<SelectListItem>();

            foreach (var item in list)
            {
                selectList.Add(new SelectListItem { Text = item.Name, Value = item.Name});
            }

            ViewBag.Items = selectList;

            return View();
        }