CODEWITHSUNDEEP
c#asp.net-mvcentity-frameworklinq
Nicolas
Nicolas

Reputation: 4756

C# - The entity or complex type cannot be constructed in a LINQ to Entities query

I'm trying to send data with a view and print it out, but I'm struggling really hard since I'm very new to C#.

So here's my model ViewModel:

namespace P104.Models
{
    public class ViewModel
    {
    }

    public class Location
    {
        public int loc_id { get; set; }
        public string loc_name { get; set; }
    }

    public class Competentie
    {
        public int Comp_id { get; set; }
        public string competentie { get; set; }
    }

    public class MyViewModel
    {
        public User User { get; set; }
        public IEnumerable<Locations> Locations { get; set; }
        public IEnumerable<Competenties> Competenties { get; set; }
    }
}

This is the function I have in the controller

public ActionResult Details(int? id)
{
    if (id == null)
    {
        return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
    }
    User user = db.user.Find(id);

    if (user == null)
    {
        return HttpNotFound();
    }

    var competenties =
        from usercomp in dbE.UserComp
        join comp in dbE.Competenties on usercomp.fk_Comp_id equals comp.comp_id
        where usercomp.fk_user_id == id
        select new Competenties { competentie = comp.competentie };

    var locations =
        from userloc in dbE.UserLoc
        join loc in dbE.Locations on userloc.fk_location_id equals loc.loc_id
        where userloc.fk_user_id == id
        select new Locations { loc_name = loc.loc_name };

    var model = new MyViewModel
    {
        User = user,
        Locations = locations.ToList(), // eagerly fetch the data that will be needed in the view
        Competenties = competenties.ToList(), // eagerly fetch the data that will be needed in the view
    };
    return View(model);
}

And he's how I try to print it out in the view:

@foreach (var location in Model.Locations)
{
    <dt>@location.locname</dt>
    <dd>@location.locname</dd>
}
@foreach (var competentie in Model.Competenties)
{
    <dt>@competentie.competentie</dt>
    <dd>@competentie.competentie</dd>
}

I always recevie this error

The entity or complex type 'P104.Models.Locations' cannot be constructed in a LINQ to Entities query.

I've found a few solutions, but I'm struggling to apply them to my code so they don't work. Thanks in advance for your help

Upvotes: 2

Views: 968

Answers (1)

Darin Dimitrov
Darin Dimitrov

Reputation: 1038800

You seem to have got a typo here:

select new Locations { loc_name = loc.loc_name };

This should be:

select new Location { loc_name = loc.loc_name };

The model you are projecting against is called Location, not Locations. It's unclear what the Locations model is since you haven't shown that in your question.

And of course adapt your view accordingly:

@foreach (var location in Model.Locations)
{
    <dt>@location.loc_name</dt>
    <dd>@location.loc_name</dd>
}

By the way I will recommend you following standard C# naming conventions. This convention dictates that in C# a property name should start with an uppercase letter and not contain _. So basically you would rather use LocationName or just Name instead of loc_name. Same remark for your Competentie model.

Upvotes: 3

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