I'm trying to create the table "Prodotti" with 2 foreing keys to itself but I keep having this error: "The ForeignKeyAttribute on property 'ProdottiRichiesti' on type 'BugTracking_Entity.Prodotti' is not valid. The navigation property 'Prodotti' was not found on the dependent type 'BugTracking_Entity.Prodotti'. The Name value should be a valid navigation property name."
This is my code:
[Key]
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public int Id { get; set; }
[ForeignKey("Prodotti")]
public virtual int ProdottiRichiesti { get; set; }
[ForeignKey("Prodotti")]
public virtual int ProdottiIncompatibili { get; set; }
using System.ComponentModel.DataAnnotations.Schema;
public class Student
{
public int StudentID { get; set; }
public string StudentName { get; set; }
[ForeignKey("Standard")]
public int StandardRefId { get; set; }
public Standard Standard { get; set; }
}
public class Standard
{
public int StandardId { get; set; }
public string StandardName { get; set; }
public ICollection<Student> Students { get; set; }
}
You have to create a Prodotti class instead of Standart like that example.
Related
Entity framework changed the column name in the DB, and isn't giving me it's value.
Here are my classes:
public class Settings
{
[Key]
public int ID { get; set; }
public string Setting { get; set; }
public string MoreDetail { get; set; }
public SettingTypes Type { get; set; }
public SettingGroups SettingGroup { get; set; }
public int? MinMembership { get; set; }
public string DefaultValue { get; set; }
public int? ParentID { get; set; }
public int Order { get; set; }
}
public class SettingTypes
{
[Key]
public int ID { get; set; }
[MaxLength(35)]
public string TypeName { get; set; }
}
public class SettingGroups
{
[Key]
public int ID { get; set; }
[MaxLength(35)]
public string GroupName { get; set; }
}
In the DB you can see that it changed the name of the two columns:
When I try to loop through the results, type is null:
How do I retrieve this value? I've tried renaming the columns in the class and in the DB but that just breaks more things. What's the proper way to handle this?
Thanks!
Dangit, I figured it out. Spent way to much time doing so.
It was as simple as adding "virtual" to the properties:
public virtual SettingTypes Type { get; set; }
public virtual SettingGroups SettingGroup { get; set; }
Now I can address it like:
setting.Type.TypeName
Hope this saves someone else some time.
I have Country, City, Region and "Account Address" tables.
I want to create foreign key columns in "Account Address" pointing to Country, City, Region tables.
I have this code but it throws an error on creating database
The property \u0027Account_Id\u0027 cannot be configured as a
navigation property. The property must be a valid entity type and the
property should have a non-abstract getter and setter. For collection
properties the type must implement
After New Edit
public class Cities
{
[Key]
public int City_Id { get; set; }
public string City_name { get; set; }
public int Country_Id { get; set; }
[ForeignKey("Country_Id")]
public Countries countries { get; set; }
}
public class Region
{
[Key]
public int Region_Id { get; set; }
public string Region_name { get; set; }
public int City_Id { get; set; }
[ForeignKey("City_Id")]
public Countries countries { get; set; }
}
public class Accounts
{
[Key]
public int Account_Id { get; set; }
public string Fullname { get; set; }
public string Email { get; set; }
public string password { get; set; }
public int Cell_phone { get; set; }
public string Role { get; set; }
public int? estate_office_Id { get; set; }
[ForeignKey("estate_office_Id")]
public Estate_office estate_office { get; set; }
public List<Ads> ads { get; set; }
}
public class Account_address
{
[Key]
public int Id { get; set; }
[ForeignKey("Account_Id"), Column(Order = 0)]
public int Account_Id { get; set; }
[ForeignKey("Country_Id"), Column(Order = 1)]
public int Country_Id { get; set; }
[ForeignKey("City_Id"), Column(Order = 2)]
public int City_Id { get; set; }
[ForeignKey("Region_Id"), Column(Order = 3)]
public int Region_Id { get; set; }
public Accounts accounts { get; set; }
public Countries countries { get; set; }
public Cities cities { get; set; }
public Region region { get; set; }
}
You need to define public properties as shown below on the Account_address class.Then only EF will know how to map those navigation properties correctly.
public class Account_address
{
......
......
public Accounts accounts { get; set; } //like this
public Countries countries { get; set; } //like this
public Cities cities { get; set; } //like this
public Region region { get; set; } //like this
}
Update :
Hence you're not using singular naming convention for the classes,you have encountered this issue.Either you have to change the name of classes as singular or need to change the navigational property names a shown below.You have to do this for all the places.Here I have shown only for the Accounts class related navigational property.
[ForeignKey("Accounts_Id"), Column(Order = 0)]
public int Accounts_Id { get; set; }
My Advice is to follow the basic naming conventions.Then you can avoid lot of above kind of weird errors.
This question already has an answer here:
MVC 4 Code First ForeignKeyAttribute on property ... on type ... is not valid
(1 answer)
Closed 6 years ago.
I am using entity framework code first and added a class that has a list of classes of which the classes also have to have another list of classes but when I try to do an update to the database through migrations I get this:
The ForeignKeyAttribute on property 'SubscaleStatistics' on type SubscaleScore' is not valid. The foreign key name 'SubscaleStatisticsId' was not found on the dependent type 'SubscaleScore'. The Name value should be a comma separated list of foreign key property names.
Here's what my classes look like:
public class ExamStatistics : StatisticsData
{
[Key]
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public int Id { get; set; }
[Required]
public int TestId { get; set; }
public IList<SubscaleStatistics> Subscales { get; set; }
}
public class SubscaleStatistics
{
[Key]
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public int SubscaleStatisticsId { get; set; }
public int TestId { get; set; }
public int SubscaleNumber { get; set; }
public int ExamStatisticsId { get; set; }
[ForeignKey("ExamStatisticsId")]
public virtual ExamStatistics ExamStatistics { get; set; }
public IList<SubscaleScore> SubscaleScores { get; set; }
}
public class SubscaleScore
{
public int TestId { get; set; }
public int Subscale { get; set; }
public double Score { get; set; }
public int SubscaleId { get; set; }
[ForeignKey("SubscaleStatisticsId")]
public virtual SubscaleStatistics SubscaleStatistics { get; set; }
}
What am I doing wrong here? Or do I need to provide more information to get what's wrong?
You need to add a foreign key property to SubscaleScore.
public int SubscaleStatisticsId { get; set; }
see here for tutorial: foreign keys
the foreignkey must be a id not the object
try something like this:
public class SubscaleScore
{
public int TestId { get; set; }
public int Subscale { get; set; }
public double Score { get; set; }
public int SubscaleId { get; set; }
[ForeignKey("SubscaleStatisticsId")]
public int SubscaleStatisticsId { get; set; }
public virtual SubscaleStatistics SubscaleStatistics { get; set; }
}
do the same for all classes with foreignkey
I'm experiencing an unexpected error when setting up a migration after adding keys and foreign keys to my data model. I'm using VS2013 Express, with .NET framework 4.5.
When creating a data model for Entity Framework, because the relationship keys between classes aren't what is expected by convention, I'm using data annotations as outlined in the MS Data Developer Center. Here's the class code:
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
namespace BacklogTracker.Models
{
public class WorkOrder
{
[Key]
public string woNum { get; set; }
public string woClosingStatus { get; set; }
[ForeignKey("ID")]
public virtual ICollection<Note> woNotes { get; set; }
[ForeignKey("machSN")]
public virtual Machine woMachine { get; set; }
[ForeignKey("ID")]
public virtual ICollection<Segment> woSegments { get; set; }
}
public class Machine
{
[Key]
public string machSN { get; set; }
public string machLocation { get; set; }
public string machModel { get; set; }
}
public class Segment
{
[Key]
public int ID { get; set; }
public uint segNum { get; set; }
public string segRepair { get; set; }
[ForeignKey("ID")]
public virtual ICollection<Note> segNotes { get; set; }
}
public class Note
{
[Key]
public int ID { get; set; }
public DateTime notetimestamp { get; set; }
public string notestring { get; set; }
}
}
However, when I try to perform a migration after updating the model by performing enable-migrations in the package manager console, I get the following error:
The ForeignKeyAttribute on property 'woMachine' on type
'BacklogTracker.Models.WorkOrder' is not valid. The foreign key name
'machSN' was not found on the dependent type
'BacklogTracker.Models.WorkOrder'. The Name value should be a comma
separated list of foreign key property names.
Why is my foreign key name 'machSN' not being found?
I think you have some errors in your model. Default Code First convention for ForeignKey relationship expected to have declared a foreign key property in the dependend end (WorkOrder) that match with primary key property of the principal end (Machine). It is not necessary that they have the same name, check this link. So, declare a property named machSN in your WorkOrder class:
public class WorkOrder
{
[Key]
public string woNum { get; set; }
public string woClosingStatus { get; set; }
public virtual ICollection<Note> woNotes { get; set; }
public string machSN { get; set; }
[ForeignKey("machSN")]
public virtual Machine woMachine { get; set; }
public virtual ICollection<Segment> woSegments { get; set; }
}
You can find other errors in the woNotes and woSegments navigation properties. In this side of a one-to-many relationship you don't declare a FK, is in the other side, in Note and Segment classes, for example:
public class Note
{
[Key]
public int ID { get; set; }
public DateTime notetimestamp { get; set; }
public string notestring { get; set; }
[ForeignKey("Order)]
public string woNum { get; set; }
public virtual WorkOrder Order{get;set;}
}
Delete also in the Segment class the ForeignKey attribute over segNotes navigation property for the same reasons explained before.
public class Segment
{
[Key]
public int ID { get; set; }
public uint segNum { get; set; }
public string segRepair { get; set; }
public virtual ICollection<Note> segNotes { get; set; }
}
I have the following model using EF6, where I'm trying to link a 'ContentArticleHOAsubdivision' entity to a 'SubdivisionHOA':
public partial class ContentArticleHOAsubdivision
{
public int Id { get; set; }
[ForeignKey("ContentArticleHOA")]
public long ContentArticleId { get; set; }
[ForeignKey("SubdivisionsHOA")]
public short SubdivisionId { get; set; }
public virtual ContentArticleHOA ContentArticleHOA { get; set; }
public virtual ICollection<SubdivisionHOA> SubdivisionsHOA { get; set; }
}
public partial class SubdivisionHOA
{
public short Id { get; set; }
public string Name { get; set; }
[ForeignKey("TopTierDivisionHOA")]
public byte TopTierDivisionId { get; set; }
public virtual TopTierDivisionHOA TopTierDivisionHOA { get; set; }
}
I get the error:
The foreign key component 'SubdivisionId' is not a declared property on type 'SubdivisionHOA'. Verify that it has not been explicitly excluded from the model and that it is a valid primitive property.
The 'Id' property in SubdivisionHOA I'm trying to link on needs to be named 'Id' as that's the name of the actual column in the database, so I'm not sure what I need to do?
I've tried adding [InverseProperty("Id")] before the [ForeignKey] attributes but get the same error.
Basicly the foreign key usage in EntityFramework seems like this:
public partial class ContentArticleHOAsubdivision
{
public int Id { get; set; }
...
public virtual ICollection<SubdivisionHOA> SubdivisionsHOAs { get; set; }
}
public partial class SubdivisionHOA
{
public short Id { get; set; }
...
public int ContentArticleHOAsubdivisionId { get; set; }
[ForeignKey("ContentArticleHOAsubdivisionId")]
public virtual ContentArticleHOAsubdivision ContentArticleHOAsubdivision { get; set; }
}
Just based on your code, and I have discard some unknown stuffs.