I have a model enrollment that have a list of components that have a list of subcomponents. This is what i have:
public class Enrollment
{
...
public virtual int ClassroomId { get; set; }
public virtual Classroom Classroom { get; set; }
public virtual List<Components> Components { get; set; }
}
public class Component
{
...
public virtual int EnrollmentId { get; set; }
public virtual Enrollment Enrollment{ get; set; }
public virtual List<Subcomponent> Subcomponents { get; set; }
}
public class Subcomponent
{
...
public virtual int ComponentId { get; set; }
public virtual Component Component{ get; set; }
public virtual List<Subcomponent> Subcomponent { get; set; } (???)
}
The user needs to be able to create subsubcomponents and so on, as much as he wants. For example, the enrollment Matematics have a component Test that have a subcomponent Group1 that can have a subsubcomponent Question 1 and a subsubsubcomponent Question 1.1 and so on.
I have this create methods on the Subcomponent controller:
public ActionResult CreateMoreSubcomponents(int id)
{
var x = db.Subcomponents.FirstOrDefault(e => e.SubcomponentId == id);
if (x == null)
{
return HttpNotFound();
}
var subcomponent = new Subcomponent()
{
ComponentId = x.ComponentId,
SubcomponentId = x.SubcomponentId
};
return View("CreateMoreSubcomponents", subcomponent);
}
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult CreateMoreSubcomponents(Subcomponent subcomponent)
{
if (ModelState.IsValid)
{
db.Subcomponents.Add(subcomponent);
db.SaveChanges();
return RedirectToAction(...);
}
return View(subcomponent);
}
Note that this code may be all wrong, this was just a way i tried to do. The question is how can i do it? Am i close to the solution or not so close and if so how is it possible to do what i want? Thanks
EDIT:
I changed the code since it needs the componentId anyways. In this way it gives me an error on db.SaveChanges();
The INSERT statement conflicted with the FOREIGN KEY constraint "FK_dbo.Subcomponents_dbo.Components_ComponentId". The conflict occurred in database "SGPContext-20160719133511", table "dbo.Components", column 'ComponentId'. The statement has been terminated
Related
I have a code block regards get a list like that in aspnetzero:
public async Task<List<DMNCCThueSuatDto>> GetDSThueSuat()
{
using (_unitOfWorkManager.Current.SetTenantId(null))
{
var lstthueSuat = await _dmThueSuatRepository.Query(t => t.Where(i =>
i.IsDeleted == false)).OrderBy("thuesuat_ma asc").ToListAsync();
return ObjectMapper.Map<List<DMNCCThueSuatDto>>(lstthueSuat);
}
}
I expected a list of DMNCCThueSuatDto is returned but the error
Cannot create a DbSet for 'DM_NCC_ThueSuat' because this type is not
included in the model for the context.
is always displayed.
Also, i had myown a declaration
public virtual DbSet DS_ThueSuat { get; set; }
in my DBContext.
In my mariadb database, i had a table called "vs_dm_ncc_thuesuat"
and i have already declare a class for mapping to the table above
namespace VS.vHoaDon.Domains.DanhMuc.DMNhaCungCap
{
[Table("vs_dm_ncc_thuesuat")]
[MultiTenancySide(MultiTenancySides.Host)]
public class DM_NCC_ThueSuat : FullAuditedEntity
{
public int ThueSuat_Ma { get; set; }
public string ThueSuat_Ten { get; set; }
public int ThueSuat_GiaTri { get; set; }
public bool ThueSuat_HieuLuc { get; set; }
public DateTime? ThueSuat_BatDau { get; set; }
public DateTime? ThueSuat_KetThuc { get; set; }
}
}
I don't know why?
Any helps is appreciated.
Thank you so much.
I'm playing with new ASP.Net 5.0 WebApi and strugling to understand how to return more then one child object, or child of the child.
Lets say I have 4 classes:
public class Car
{
public int Id { get; set; }
public string Name { get; set; }
public int TypeId { get; set; }
public int ColourId { get; set; }
public virtual Type Type { get; set; }
public virtual Colour Colour { get; set; }
}
public class Type
{
public int Id { get; set; }
public string Name { get; set; }
public int TypeGroupId { get; set; }
public virtual TypeGroup TypeGroup { get; set; }
}
public class Colour
{
public int Id { get; set; }
public string Name { get; set; }
}
public class TypeGroup
{
public int Id { get; set; }
public string Name { get; set; }
}
And would like to return all the data for the car including Type, Colour, and even TypeGroup of the Type. How do I Do it?
When I do like this it includes only Type:
[HttpGet]
public IEnumerable<Car> Get()
{
return _dbContext.Cars.Include(c => c.Type);
}
This is my setup in Startup.cs:
services.AddMvc().AddJsonOptions(options =>
{
options.SerializerSettings.ContractResolver =
new CamelCasePropertyNamesContractResolver();
options.SerializerSettings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore;
});
Is it possible to set to return every child object and grandchild and etc?
Many thanks
You can turn off lazy loading for all entities by using the following in your DbContext class (place this in the constructor):
this.Configuration.LazyLoadingEnabled = false;
This will disable it for all entities - so be wary of this and watch for performance issues.
Another way you can load all the entities for a particular class is to remove the virtual keyword from the property declarations.
This question is in reference to the project discussed here. After resolving the previous problem I have run into a new one. When The Student object is saved, the list of courses associated with it is not saved. I can see the collection of course objects when I mouse over the student object after setting a breakpoint:
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult AddCourseVM (AddCourseViewModel vModel)
{
Student stu = db.Students.Find(vModel.Student.ID);
foreach (Course c in vModel.PossibleCourses)
{
if (c.Selected)
{
BaseCourse bc = db.BaseCourses.Find(c.BaseCourse.ID);
c.BaseCourse = bc;
c.Student = stu;
stu.CoursesTaken.Add(c);
}
}
if (stu != null)
{
db.Entry(stu).State = EntityState.Modified; //breakpoint here
db.SaveChanges();
}
return RedirectToAction("ListTakenCourses", stu);
}
public ActionResult ListTakenCourses (Student stu)
{
List<Course> taken = stu.CoursesTaken.ToList();
foreach (Course c in taken)
{
c.BaseCourse = db.BaseCourses.Find(c.BaseCourse.ID);
}
ViewBag.CoursesTaken = taken;
return View(stu);
}
But when I pass the object to the next method, the list of courses taken comes back null. The courses are being saved to the database, I can see them when I go into the SQL Server explorer, but for some reason they are not being attached to the student object. The code for the objects:
public class Student
{
public int ID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string WNumber { get; set; }
public int HoursCompleted { get; set; }
public double GPA { get; set; }
public Concentration StudentConcentration { get; set; }
public virtual ICollection<Course> CoursesTaken { get; set; }
public virtual ICollection<Course> CoursesRecommended { get; set; }
}
and:
public class Course
{
public int ID { get; set; }
public string Semester { get; set; }
public Grade? Grade { get; set; }
public bool Selected { get; set; }
public BaseCourse BaseCourse { get; set; }
public Student Student { get; set; }
}
Something that may be important, but that I don't really understand: when I look at the table for the Course object in the database, there are three columns, called Student_ID, Student_ID1, and Student_ID2. I assume they relate to the student associated with the object and the two ways it can be associated (recommended or taken), but the odd thing is that Student_ID is always null, while the other two sometimes have a value and sometimes do not. I have not even begun to implement the recommendation process, so there is no way that list is being filled.
I reworked the classes and now it seems to be working. I changed the Course object to:
public class Course
{
public int ID { get; set; }
public string Semester { get; set; }
public Grade? Grade { get; set; }
public bool Selected { get; set; }
public int BaseCourseID { get; set; }
public int StudentID { get; set; }
public BaseCourse BaseCourse { get; set; }
public Student Student { get; set; }
}
and the controller methods to:
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult AddCourseVM (AddCourseViewModel vModel)
{
Student stu = db.Students.Find(vModel.Student.ID);
foreach (Course c in vModel.PossibleCourses)
{
if (c.Selected)
{
BaseCourse bc = db.BaseCourses.Find(c.BaseCourse.ID);
c.BaseCourse = bc;
c.Student = stu;
stu.CoursesTaken.Add(c);
db.Entry(c).State = EntityState.Added;
}
}
if (stu != null)
{
db.Entry(stu).State = EntityState.Modified;
db.SaveChanges();
}
return RedirectToAction("ListTakenCourses", stu);
}
public ActionResult ListTakenCourses (Student stu)
{
List<Course> taken = db.Courses.Where(c => c.StudentID == stu.ID).ToList();
foreach (Course c in taken)
{
c.BaseCourse = db.BaseCourses.Find(c.BaseCourseID);
c.Student = stu;
stu.CoursesTaken.Add(c);
}
ViewBag.CoursesTaken = taken;
return View(stu);
}
And it is now displaying the courses I add on the next page, but it seems odd that I have to save the child objects separately from the parent and that I have to get the list from the database manually instead of being able to use the object structure. Is this intended behavior, or is there a better way of doing what I'm trying to do (add a list of child objects (courses) to a student object, save the relationship to the database, and then display the list of added objects)?
You are not "passing the object to the next method". You are serializing the object and passing it on the URL, then deserializing it on the other end with this method:
return RedirectToAction("ListTakenCourses", stu);
This is not the way to go about things. What you should be doing is passing a single id, such as the student id. Then, in ListTakenCourses you look up the student again in the database, which if you are doing your query correctly will fully populate the objects.
return RedirectToAction("ListTakenCourses", new { id = stu.StudentID });
public ActionResult ListTakenCourses (int id)
{
List<Course> taken = db.Courses.Where(c => c.StudentID == id).ToList();
//...
}
Could somebody please provide an example of how to combine two models within one view?
Currently I have a page called RecordCard which contains:
#model IEnumerable<WebApplication1.Models.Weight>
This is provided by the following code in the AccountController:
public ActionResult RecordCard()
{
var UserId = User.Identity.GetUserId();
var weightModel = from m in db.Weights where m.UserId == UserId select m;
return View(weightModel);
}
The RecordCard page also contains a form which is bound to the following class:
public class AddWeightModel
{
[Required]
[DataType(DataType.Text)]
[Display(Name = "Stone")]
public Nullable<short> Stone { get; set; }
[Required]
[DataType(DataType.Text)]
[Display(Name = "Pound")]
public Nullable<short> Pound { get; set; }
}
However, these are two individual models with different purposes, so how do I combine to a single model that contains an IEnumerable list and set of form elements that will ultimately post to the AccountController correctly to add a record to the database using the following code:
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult RecordCard(Weight Model)
{
if (ModelState.IsValid)
{
using (WebApplication1Entities db = new WebApplication1Entities())
{
Weight weight = new Weight();
weight.UserId = User.Identity.GetUserId();
weight.Stone = Model.Stone;
weight.Pound = Model.Pound;
weight.Date = System.DateTime.Now;
db.Weights.Add(Model);
db.SaveChanges();
}
}
return View(Model);
}
I have included the Weight class below:
public partial class Weight
{
public int Id { get; set; }
public string UserId { get; set; }
public Nullable<short> Stone { get; set; }
public Nullable<short> Pound { get; set; }
public Nullable<System.DateTime> Date { get; set; }
}
Also here is the WebApplication1Entities class which declares the Weight table as Weights:
public partial class WebApplication1Entities : DbContext
{
public WebApplication1Entities()
: base("name=WebApplication1Entities")
{
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
throw new UnintentionalCodeFirstException();
}
public virtual DbSet<Weight> Weights { get; set; }
}
Please explain what needs to be modified and how, no matter what I try to read, follow and implement, I seem to be missing something.
Any help would be much appreciated :-)
I would say this is good example of using ViewModel here. I would suggest something like -
Create ViewModel with the composition of the two classes
public class AddWeightModel
{
[Required]
[DataType(DataType.Text)]
[Display(Name = "Stone")]
public Nullable<short> Stone { get; set; }
[Required]
[DataType(DataType.Text)]
[Display(Name = "Pound")]
public Nullable<short> Pound { get; set; }
}
....
public partial class Weight
{
public int Id { get; set; }
public string UserId { get; set; }
public Nullable<short> Stone { get; set; }
public Nullable<short> Pound { get; set; }
public Nullable<System.DateTime> Date { get; set; }
}
.....
public class WeightViewModel
{
public IList<AddWeightModel> AddWeightModel { get; set; }
public Weight Weight { get; set; }
}
Then change your view to accept the view models -
#model WeightViewModel
Finally modify your controller to cope with the change -
public ActionResult RecordCard()
{
var UserId = User.Identity.GetUserId();
var weightModel = from m in db.Weights where m.UserId == UserId select m;
var viewModel = new WeightViewModel
{
Weight = weightModel,
AddWeightModel = new List<AddWeightModel>(){}
};
return View(viewModel);
}
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult RecordCard(WeightViewModel viewModel)
{
Weight Model = viewModel.Weight;
if (ModelState.IsValid)
{
using (WebApplication1Entities db = new WebApplication1Entities())
{
Weight weight = new Weight();
weight.UserId = User.Identity.GetUserId();
weight.Stone = Model.Stone;
weight.Pound = Model.Pound;
weight.Date = System.DateTime.Now;
db.Weights.Add(Model);
db.SaveChanges();
}
}
return RedirectToAction("RecordCard");
}
I've tackled this before, can came to an elegant solution.
First, you'd want to setup your main classes to send, as well as a 'holder' class to store them to eventually send to a view.
As you probably found out, this is because a view can't have multiple models sent to it.
public class WebsiteTheme
{
public string Color { get;set; }
public string Title { get;set; }
public WebsiteTheme() {
Color = "blue";
Title = "test website";
}
}
public class User
{
public string Name { get;set; }
public string Gender { get;set; }
public User() {
Name = "Anonymous";
Gender = "Unspecified";
}
}
public class ToPage
{
public WebsiteTheme WebsiteTheme{ get; set; }
public User User { get; set; }
public ToPage() {
websiteTheme = new WebsiteTheme();
user = new User();
}
}
This will allow you to send any amount of classes to your page.
Then, in your controller, you'd want to populate those classes. Make sure to initialise them all first, then set the populated classes to your holder class.
WebsiteTheme websiteTheme = new WebsiteTheme();
websiteTheme.Color = "orange";
User user = new User();
user.Name = "Darren";
ToPage toPage = new ToPage();
toPage.User = user;
toPage.WebsiteTheme = websiteTheme;
return View(toPage);
In your view, you'd call them in any way you want to. But make sure to use HolderModel.SpecifiedModel in every case.
#model WebApplication1.Models.ToPage
#Html.DisplayFor(model => model.User.Name)
I did a compound model like this:
public class CompoundModel
{
public SearchModel SearchModel { get; set; }
public QueryResultRow ResultModel { get; set; }
}
public class QueryResultRow
{
[DisplayName("Id")]
public long id { get; set; }
[DisplayName("Importdatum")]
public System.DateTime importdate { get; set; }
[DisplayName("Mandant")]
public int indexBMClient { get; set; }
}
public class SearchModel
{
[Required]
[DataType(DataType.Date)]
[Display(Name = "Zeitraum von")]
public DateTime dateFrom { get; set; }
[Display(Name = "Terminal-ID")]
public string tid { get; set; }
[Display(Name = "Belegnummer")]
public string receiptnumber { get; set; }
}
In the view header:
#model MyProject_aspmvc.Models.CompoundModel
And get data access from the SearchModel, for example:
model => model.SearchModel.tid
and data access from the ResultModel, for example:
model => model.ResultModel.importdate
I'm wondering what's the best way to handle default values for relationships when making models. (Specifically EF4)
For example, my Organization has a default Contact and I was wondering which one was the best approach. I got these two options (or any other anyone suggests if better)
Using Relationship:
public class Contact
{
public int Id { get; set; }
public string FirstName { get; set; }
}
public class Organization
{
public int Id { get; set; }
public string Name { get; set; }
public ICollection<Contact> Contacts { get; set; }
//Use a relationship for the default contact?
public Contact DefaultContact { get; set; }
}
Using Value:
public class Contact
{
public int Id { get; set; }
public string FirstName { get; set; }
//Use value?
public boolean IsDefault { get; set; }
}
public class Organization
{
public int Id { get; set; }
public string Name { get; set; }
public ICollection<Contact> Contacts { get; set; }
}
I'd go with Option 1. While 2 is definitely easier to implement, it doesn't enforce rules such as "There cannot be 2 default contacts". I end up with something like the following:
public class Organization {
// ...
public virtual ICollection<Contact> { get;set; }
[ForeignKey("DefaultContactId")]
public Contact DefaultContact { get;set; }
public int? DefaultContactId { get;set; }
}
There's a limitation of this approach - it doesn't work nested deletes (see this question for more details). Because of this, you need to disable CascadeOnDelete for the 1-to-many relationship:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Contact>().HasRequired(co => co.Organization).WithMany().WillCascadeOnDelete(false);
}
(Code done without testing, but should work)
The other problem with this is that it's not possible to add the Default Contact at the same time as you're adding the organization, as EF can't figure out the correct order of statements. You need to call .SaveChanges between each. You can still use a TransactionScope to overcome this, but it's not clean:
using (var ts = new TransactionScope())
{
Organization org = new Organization
{
// ...
Contacts = new Collection<Contact>()
}
org.Contacts = new Contact() {};
orgRepo.SaveChanges();
// Now wire up the default contact
org.DefaultContact = org.Contacts.First();
orgRepo.SaveChanges();
}