Simple DropDownList in ASP.NET MVC3 app - asp.net

Question

I need simple DropDownList in form and I don't want to create something like ViewModel.
I have two models(tables) in relation 1:n:
public class Course
{
public int ID { get; set; }
public string Name { get; set; }
}
and
public class Project
{
public int ID { get; set; }
public int CourseId { get; set; }
public int ProjectNo { get; set; }
public string Name { get; set; }
public DateTime Deadline { get; set; }
}
In the 'Create Project' I want to have DropDownList with Id (as value) and Name(as text) from Course table(model). In the new project will be insert chosen CourseId. How can I do that as simple as possible?

Answer 1

Any particular reason why you don't want to use a ViewModel? They're very helpful for this type of problem.
If you don't want to use a ViewModel, then you can construct a specific class in your controller that is an aggregate of the properties you need from both classes:
public ActionResult Show(int id)
{
Course course = repository.GetCourse(id); // whatever your persistence logic is here
Project project = projectRepository.GetProjectByCourseId(id);
string CourseName = from c in course where
c.ID == project.courseID
select c.Name;
IEnumerable<SelectListItem> selectList =
from c in course
select new SelectListItem
{
Selected = (c.ID == project.CourseId),
Text = c.Name,
Value = project.CourseId.ToString()
};
//add the selectList to your model here.
return View(); //add the model to your view and return it.
}
It would be far easier to have a ViewModel for this, so you could have a strongly typed view. Let me show you:
public class ProjectCourseViewModel
{
public SelectList ProjectCourseList {get; private set; }
public Project Project {get; private set; }
public Course Course {get; private set; }
public ProjectCourseViewModel(Project project, Course course)
{
ProjectCourseList = GetProjectCourseSelectList(project, course)
Project = project;
Course = course;
}
private SelectList GetProjectCourseSelectList(Project project, Course course)
{
IEnumerable<SelectListItem> selectList =
from c in course
select new SelectListItem
{
Selected = (c.ID == project.CourseId),
Text = c.Name,
Value = project.CourseId.ToString()
};
}
}
And then your controller would be really simple:
public ActionResult Show(int id)
{
Course course = repository.GetCourse(id);
Project project = projectRepository.GetProjectByCourseId(id);
ProjectCourseViewModel pcvm = new ProjectCourseViewModel(project, course)
return View(pcvm);
}
And then your view takes in a strongly typed model, and you don't have to rely on ViewData, which is a Good Thing.
Note: I haven't compiled this, just written it. There are probably compilation bugs.

Answer 2

probably you could solve it using the following example:
in your controller include a Viewbag
{
Viewbag.Course = db.course.ToList();
var project = new project.....
}
And in your View use the following pattern:
#Html.DropDownList("CourseId",
new SelectList(ViewBag.Course as System.Collections.IEnumerable,
"CourseId", "Name", Model.ID))
where each field represent:
•The name of the form field (CourseId)
•The list of values for the dropdown, passed as a SelectList
•The Data Value field which should be posted back with the form
•The Data Text field which should be displayed in the dropdown list
•The Selected Value which is used to set the dropdown list value when the form is displayed
more info at: http://www.asp.net/mvc/tutorials/mvc-music-store-part-5
brgds.

Answer 3

In the Controler:
var CourseName = from c in course where
c.ID == project.courseID
select c.Name;
SelectList sl = new SelectList(CourseName);
ViewBag.names= sl;
in the view :
#Html.DropDownList("Name", (SelectList)ViewBag.names)