i've been working with DTOs lately and am unable to determine the issue that this code is having.
I'm mapping Genre names and Movie names to a GenreMovieDto. Visual Studio doesn't show any errors (red lines etc) but when the code is run I get the following:
$exception {"The specified type member 'Movies' is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported."} System.NotSupportedException
My code is the following:
public class Genre
{
public int Id { get; set; }
public string Name { get; set; }
public IEnumerable<Movie> Movies { get; set; }
}
public class Movie
{
public int Id { get; set; }
public string Name { get; set; }
public string AgeRating { get; set; }
public int NumberInStock { get; set; }
public Genre Genre { get; set; }
}
public class GenreMovieDto
{
public string GenreName { get; set; }
public IEnumerable<Movie> Movies { get; set; }
}
And my API call:
public IEnumerable<GenreMovieDto> GetGenresWithMovies()
{
var genresWithMovies = _context.Genres
.Include(m => m.Movies)
.Select(x => new GenreMovieDto
{
GenreName = x.Name,
Movies = x.Movies <<<<< CRASHES HERE
})
.ToList();
return genresWithMovies;
}
Any thoughts ? Any and all suggestions / criticism is welcome :P I'm here to learn.
Thanks in advance
You can do like this (EF doesn't support IEnumerable<...> type member):
public class Genre
{
public int Id { get; set; }
public string Name { get; set; }
public virtual List<Movie> Movies { get; set; }
}
Related
I am trying to get this expression working in my Razor file:
<span>#($" ({string.Join(", ", from o in comment.CommentStaff.StaffOffices select o.Office.OfficeOrganizationCd)})")</span>
But it says "Query expressions over source type 'dynamic' or with a join sequence of type 'dynamic' are not allowed" in the red squiggly in the Razor and the Developer exception page.
Here is my model (#model CommentVM) coming down to the Razor from the controller action:
public class CommentVM
{
public int AuditId { get; set; }
public string Comment { get; set; }
public IEnumerable<Comment> Comments { get; set; }
}
Here is the Controller Action (actually this is coming from the Invoke method in a component. But this shouldn't really make a difference).
public IViewComponentResult Invoke(int auditId)
{
IQueryable<Comment> comments = _commentRepo.Comments.Include(c => c.CommentStaff).ThenInclude(c => c.StaffOffices)
.Where(c => c.CommentAuditId == auditId)
.OrderByDescending(c => c.CommentDate).Take(3);
CommentVM commentVM = new CommentVM
{
AuditId = auditId,
Comments = comments
};
return View(commentVM);
}
The Comments Repo returns an IQueryable of Comment objects.
The Comment POCO looks like this:
[Table("comment")]
public class Comment
{
[Key]
[Column("comment_id")]
public int CommentId { get; set; }
[Column("comment_type_cd")]
public string CommentTypeCd { get; set; }
[Column("comment_audit_id")]
public int? CommentAuditId { get; set; }
[Column("comment_finding_id")]
public int? CommentFindingId { get; set; }
[Column("comment_recommend_id")]
public int? CommentRecommendId { get; set; }
[Column("comment_action_item_id")]
public int? CommentActionItemId { get; set; }
[Column("comment_acd_id")]
public int? CommentAcdId { get; set; }
[Column("comment_pdl_id")]
public int? CommentPdlId { get; set; }
[Column("comment_cost_nm")]
public string CommentCostNm { get; set; }
[Required]
[Column("comment_tx")]
public string CommentText { get; set; }
[Column("comment_dt")]
public DateTime CommentDate { get; set; }
#region Navigation Properties
[Column("comment_staff_id")]
public short CommentStaffId { get; set; }
[ForeignKey("CommentStaffId")]
public Staff CommentStaff { get; set; }
#endregion
}
So CommentStaff is a navigation property to a Staff object which has a bridge table POCO called StaffOffices for a many to many relationship between Staff and Office.
Here is the bridge table POCO:
[Table("staff_office")]
public class StaffOffice
{
[Column("staff_office_staff_id")]
public short ID { get; set; }
public Staff Staff { get; set; }
[Column("staff_office_office_id")]
public short OfficeID { get; set; }
public Office Office { get; set; }
}
I am trying to get this:
<span>#($" ({string.Join(", ", from o in comment.CommentStaff.StaffOffices select o.Office.OfficeOrganizationCd)})")</span>
or this:
#{
StringBuilder sb = new StringBuilder();
foreach(var o in comment.CommentStaff.StaffOffices)
{
sb.Append(o.Office.OfficeOrganizationCd);
}
}
<span>#sb.ToString()</span>
It's a partial view. I needed to include the model definition of the parent Razor file:
#model CommentVM
I am (trying to) build a multiple choice test application that will pass a list of multiple choice questions (select lists) from the controller to a view.
Then populate the view using a foreach loop, post the answers back to the controller, check them and increment the score for each correct answer and then update the db.
I am trying to populate the view model list using a Linq query (to keep my controller thin, I am doing this via a method in my Service layer).
Models
Questions (db first)
namespace AccessEsol.Models
{
using System;
using System.Collections.Generic;
public partial class Question
{
public Question()
{
this.ExamDets = new HashSet<ExamDet>();
}
public int QuID { get; set; }
public string Text1 { get; set; }
public string Text2 { get; set; }
public string CorrectAnswer { get; set; }
public string Foil1 { get; set; }
public string Foil2 { get; set; }
public string Foil3 { get; set; }
public string Level_ { get; set; }
public string GrammarPoint { get; set; }
public virtual ICollection<ExamDet> ExamDets { get; set; }
}
}
Exam
namespace AccessEsol.Models
{
using System;
using System.Collections.Generic;
public partial class Exam
{
public Exam()
{
this.Candidates = new HashSet<Candidate>();
this.ExamDets = new HashSet<ExamDet>();
}
public int ExamID { get; set; }
public string Name { get; set; }
public Nullable<System.DateTime> Date { get; set; }
public int AdminID { get; set; }
public string StartLevel { get; set; }
public virtual Administrator Administrator { get; set; }
public virtual ICollection<Candidate> Candidates { get; set; }
public virtual ICollection<ExamDet> ExamDets { get; set; }
}
}
There is also a model for Candidate that contains the CandID:
And the view model that uses these models:
namespace AccessEsol.Models
{
public class ExamQuestionsViewModel
{
public int QuID { get; set; }
public int CandID { get; set; }
public int ExamId { get; set; }
public string Text1 { get; set; }
public string Text2 { get; set; }
public string CorrectAnswer { get; set; }
public string Foil1 { get; set; }
public string Foil2 { get; set; }
public string Foil3 { get; set; }
public string Level { get; set; }
public string GrammarPoint { get; set; }
public virtual ICollection<ExamDet> ExamDets { get; set; }
}
}
This is the method that is to populate the view model:
public static List<ExamQuestionsViewModel> AddQuestions()
{
AccessEsolDataEntities db = new AccessEsolDataEntities();
string questionLevel = GetLevel();
int currentCand = GetCandID();
int currentExam = GetExamID();
//model = new DataAccess().Populate();
var qu = (from a in db.Questions
where a.Level_ == questionLevel
select a).ToList();
List<ExamQuestionsViewModel> exam = new List<ExamQuestionsViewModel>();
foreach (var IDs in exam)
{
currentCand = exam.CandID;
currentExam = exam.ExamId;
}
return (exam);
}
The error message I am getting is
'System.Collections.Generic.List<AccessEsol.Models.ExamQuestionsViewModel>'
does not contain a definition for 'ExamId' and no extension method
'ExamId' accepting a first argument of type
'System.Collections.Generic.List<AccessEsol.Models.ExamQuestionsViewModel>' could be found (are you missing a using directive or an assembly
reference?
What am I doing wrong here? All feedback much appreciated.
Please try this instead of your foreach:
foreach (var IDs in exam)
{
currentCand = IDs.CandID;
currentExam = IDs.ExamId;
}
I have a dictionary and a list.
AllMeta: is a dictionary<string, WikiMeta>
Meta: is a list<WikiMeta>
public class WikiMeta
{
public string ContentTitle { get; set; }
public string PageTitle { get; set; }
public string PageMetaDescription { get; set; }
public List<WikiArticle> Articles = new List<WikiArticle>();
public List<WikiGroup> Groups = new List<WikiGroup>();
}
public class WikiGroup
{
public string Name { get; set; }
}
I need to select values from AllMeta where AllMeta.Values.Group == Meta.Group returning a list of WikiMeta.
However, I'm struggling to construct the syntax (lambda), so any help would be appreciated.
try this:
List<WikiMeta> wikis= AllMeta.Values
.Where(allmeta =>
Meta.Any(meta=> meta.Group == allmeta.Group))
.ToList();
where I've assumed following:
public class WikiMeta
{
public string Name { get; set; }
public string Group { get; set; }
}
public IDictionary<string,WikiMeta> AllMeta { get; set; }
public List<WikiMeta> Meta { get; set; }
make sure you referenced System.Linq namespace i.e.
using System.Linq;
I am getting a weird behavior. I have a class that I created that is used to format data comping from a data entity into a data grid. I am a using a linq query to create a list of the class type from a list of the entity type. Some of the properties of the class are accessible from the linq query but other give me an error. (AMNotStartedPortalDisplay' does not contain a definition for 'ChecklistStatusID'). So my question is why can linq access some properties but not others? I see no reason why this should be happening.
Here is my class:
public class AMWOTPortalDisplay
{
public string DisplayName { get; set; }
public string LOB { get; set; }
public string DisplayProjectPackages { get; set; }
public string ChecklistStatus { get; set; }
public int ChecklistStatusID { get; set; }
public string InstallDate { get; set; }
public string dateToYellow { get; set; }
public string dateToRed { get; set; }
public string ApplicationManager { get; set; }
public string ApplicationManagerLanID { get; set; }
public int ApplicationManagerUserID { get; set; }
public string ImpersonatedManager { get; set; }
public string ImpersonatedManagerLanID { get; set; }
public int ImpersonatedManagerUserID { get; set; }
public string DelegateName { get; set; }
public string DelegateLanID { get; set; }
public int DelegateUserID { get; set; }
public string WOTAssignee { get; set; }
public int ChecklistID { get; set; }
public string DisplayLinkText { get; set; }
public string LinkTextURL { get; set; }
public string rowColor { get; set; }
public string rowTextColor { get; set; }
}
And here is the linq query as I have it so far:
var portaldisplay = checklists
.Select(c => new AMNotStartedPortalDisplay
{
DisplayName = string.Format("{0} ({1})", c.Application.Name, c.Application.ApplicationID),
LOB = c.Application.LOB,
ChecklistStatus = c.ChecklistStatusType.TypeName,
ChecklistStatusID = c.ChecklistStatusTypeID
});
Thanks,
Rhonda
Be careful with your types:
public class AMWOTPortalDisplay
And then:
Select(c => new AMNotStartedPortalDisplay { ... })
It looks like your query should probably be:
Select(c => new AMWOTPortalDisplay { ... })
I am developing an asp.net mvc application, which has these enity classes:
public class Person
{
public int PersonID { get; set; }
public string PersonPicAddress { get; set; }
public virtual List<Person_Local> PersonLocal { get; set; }
}
public class Person_Local
{
public int PersonID { get; set; }
public int CultureID { get; set; }
public string PersonName { get; set; }
public string PersonFamily { get; set; }
public string PersonAbout { get; set; }
public virtual Culture Culture { get; set; }
public virtual Person Person { get; set; }
}
public class Culture
{
public int CultureID { get; set; }
[Required()]
public string CultureName { get; set; }
[Required()]
public string CultureDisplay { get; set; }
public virtual List<HomePage> HomePage { get; set; }
public virtual List<Person_Local> PersonLocak { get; set; }
}
I defined an action with [Httppost] attribute, which accepts complex object from a view.
Here is the action :
[HttpPost]
public ActionResult CreatePerson([Bind(Prefix = "Person")]Person obj)
{
AppDbContext da = new AppDbContext();
//Only getting first PersonLocal from list of PersonLocals
obj.PersonLocal[0].Person = obj;
da.Persons.Add(obj);
da.SaveChanges();
return Jsono(...);
}
But when it throws error as below :
Exception:Thrown: "Invalid column name 'Culture_CultureID'." (System.Data.SqlClient.SqlException)
A System.Data.SqlClient.SqlException was thrown: "Invalid column name 'Culture_CultureID'."
And the insert statement :
ADO.NET:Execute Reader "insert [dbo].[Person_Local]([PersonID], [PersonName], [PersonFamily], [PersonAbout], [Culture_CultureID])
values (#0, #1, #2, #3, null)
select [CultureID]
from [dbo].[Person_Local]
where ##ROWCOUNT > 0 and [CultureID] = scope_identity()"
The command text "insert [dbo].[Person_Local]([PersonID], [PersonName], [PersonFamily], [PersonAbout], [Culture_CultureID])
values (#0, #1, #2, #3, null)
select [CultureID]
from [dbo].[Person_Local]
where ##ROWCOUNT > 0 and [CultureID] = scope_identity()" was executed on connection "Data Source=bab-pc;Initial Catalog=MainDB;Integrated Security=True;Application Name=EntityFrameworkMUE", building a SqlDataReader.
Where is the problem?
Edited:
Included EntityConfigurations Code:
public class CultureConfig : EntityTypeConfiguration<Culture>
{
public CultureConfig()
{
HasKey(x => x.CultureID);
Property(x => x.CultureName);
Property(x => x.CultureDisplay);
ToTable("Culture");
}
}
public class PersonConfig : EntityTypeConfiguration<Person>
{
public PersonConfig()
{
HasKey(x => x.PersonID);
Property(x=>x.PersonPicAddress);
ToTable("Person");
}
}
public class Person_LocalConfig : EntityTypeConfiguration<Person_Local>
{
public Person_LocalConfig()
{
HasKey(x => x.PersonID);
HasKey(x => x.CultureID);
Property(x=>x.PersonName);
Property(x => x.PersonFamily);
Property(x => x.PersonAbout);
ToTable("Person_Local");
}
}
Try to remove fields CultureID and PersonID from Person_Local class. Because you already has field Person and Culture
It looks like your schema is out of sync with your model. Make sure you understand EF Code first schema update features, which are described in this blog. If you need more sophisticated schema migration, there are some other approaches in answers to this question.