ASP.NET MVC 4 Error Saving ViewModels - asp.net-mvc

Question

Can somebody help me on how to save and update data into multiple entities using a ViewModel?
I have a ViewModel that looks like this:
public class StudentViewModel
{
public Student student;
public StudentAddress studentAddress { get; set; }
public StudentPhoto studentPhoto { get; set; }
// Three entities are related to one to one relationship
public StudentViewModel()
{ }
}
My Controller is:
[HttpPost]
public ActionResult Create(StudentViewModel studentViewModel)
{
if (ModelState.IsValid)
{
return View(studentViewModel);
}
Student s = new Student()
{
Name =studentViewModel.Student.Name,
Speciality = studentViewModel.Student.Speciality,
DateOfReg = studentViewModel.Student.DateOfJoinig,
Qualification = studentViewModel.Student.Qualification,
Email = studentViewModel.Student.Email
};
StudentAddress sa = new StudentAddress()
{
StudentId= studentViewModel.Student.StudentId,
Address = studentViewModel.StudentAddress.Address,
Area = studentViewModell.StudentAddress.Area,
City = studentViewModel.StudentAddress.City,
State = studentViewModel.StudentAddress.State,
Mobile = studentViewModel.StudentAddress.Mobile
};
StudentPhoto sp = new StudentPhoto()
{
StudentId= studentViewModel.Student.StudentId,
Photo = studentViewModel.StudentPhoto.Photo
};
db.Students.Add(s);
db.StudentAddress.Add(sa);
db.StudentPhoto.Add(sp);
db.SaveChanges();
return RedirectToAction("Home");
}
View is:
#using (Html.BeginForm()) {
#Html.ValidationSummary(true)
<fieldset>
<legend>Doctor</legend>
#Html.EditorFor(model => model.Student.Name )
#Html.EditorFor(model => model.Student.Speciality)
#Html.EditorFor(model => model.Student.DateOfJoinig)
#Html.EditorFor(model => model.Student.Standard)
#Html.HiddenFor(model => model.Student.StudentId)
#Html.EditorFor(model => model.StudentAddress.Address)
#Html.EditorFor(model => model.StudentAddress.Area)
#Html.EditorFor(model => model.StudentAddress.City)
#Html.EditorFor(model => model.StudentAddress.State)
#Html.HiddenFor(model => model.Student.StudentId)
#Html.EditorFor(model => model.StudentPhoto.Photo)
<p>
<input type="submit" value="Create" />
</p>
</fieldset>
}
<div>
#Html.ActionLink("Back to List", "Index")
</div>
I was able to retrieve and display the data (from multiple entities) into the view. However, now I'm stuck on how can I save and update the above entities with the new data. Most of the examples are 1-1 relationship the mapping is automatic, but in this case the data belongs to multiple entities.
My problem is when i try to save data it redirected to the create page. "ModelState.IsValid" is false always so no data saved. Please help me how do i proceed.
Thanks.

Answer 1

This line at the top of your Action is wrong:
if (ModelState.IsValid)
{
return View(studentViewModel);
}
It should be the opposite, only if the Model is NOT valid, then you should stop the process and re-render the View with the form.
Try:
if (!ModelState.IsValid)
{
return View(studentViewModel);
}

Answer 2

In Controller you check if(modelstate.isvalid) - if is valid you returned view without saving data from view.

Answer 3

The problem with your implementation is that your view model contains a several models(Entities). This is not a good implementation.
Try to create a viewmodel which just contains the fields (flattened version) that you want to be edited by the user when creating a student. Use Data Annotations in your view model like Required or StringLength to validate user inputs.