i'm trying create DB using codefirst. i want to create two ForeingKey from same table. But when i set up two navigation properties of the same type, get error like :
The foreign key name 'FollowedUser' was not found on the dependent type Models.UserUserWatchListItem'. The Name value should be a comma separated list of foreign key property names.
public class UserUserWatchListItem
{
public int Id { get; set; }
[Key,ForeignKey("FollowedUser")]
public virtual User FollowedUser { get; set; }
public int FollowedUserId { get; set; }
[Key,ForeignKey("FolloweeUser")]
public int FolloweeUserId { get; set; }
public virtual User FolloweeUser { get; set; }
}
Use this :
public class UserUserWatchListItem
{
public int Id { get; set; }
public int FollowedUserId { get; set; }
public int FolloweeUserId { get; set; }
[ForeignKey("FollowedUser")]
[InverseProperty("FollowedUsers")]
public virtual User FollowedUser { get; set; }
[ForeignKey("FolloweeUser")]
[InverseProperty("FolloweeUsers")]
public virtual User FolloweeUser { get; set; }
}
public class User
{
...
[InverseProperty("FollowedUser")]
public virtual ICollection<UserUserWatchListItem> FollowedUsers { get; set; }
[InverseProperty("FolloweeUser")]
public virtual ICollection<UserUserWatchListItem> FolloweeUsers { get; set; }
}
Related
I want to create a SQLite table based on the GroupEntity class which inherits from the Entity class.
When I try to create a table directly from GroupEntity class without inheritance - table creates successfully.
I am using SQLite-net, Version=1.4.118.0 in Xamarin.Forms PCL project.
public class Entity
{
public virtual int Id { get; set; }
public DateTime CreatedOn { get; set; }
public int CreatedById { get; set; }
public DateTime ModifiedOn { get; set; }
public int ModifiedById { get; set; }
}
public class GroupEntity : Entity
{
[SQLite.PrimaryKey]
public int Id { get; set; }
public string Name { get; set; }
public int PhotoFileId { get; set; }
public int UnreadMessageCount { get; set; }
public Guid LastMessageId { get; set; }
}
I have 2 classes which have a many to many relation.
public class Document
{
public int Id { get; set; }
public string Name { get; set; }
public bool AvailableOffline { get; set; }
public string URL { get; set; }
public virtual ICollection<Profile> Profiles { get; set; }
}
public class Profile
{
public int Id { get; set; }
public string Name { get; set; }
public string Description { get; set; }
public virtual ICollection<Document> Documents { get; set; }
}
On each profile I wish to have a SortOrder field for each document. So I made the joined table explicit in another class
public class ProfileDocuments
{
[Key, Column(Order = 0)]
public int DocumentId { get; set; }
[Key, Column(Order = 1)]
public int ProfileId { get; set; }
public int SortOrder { get; set; }
[ForeignKey("DocumentId")]
public virtual Document Document { get; set; }
[ForeignKey("ProfileId")]
public virtual Profile Profile { get; set; }
}
But when I update the database the table for this last class will not have a column for SortOrder. It only holds the 2 foreign keys. How can I tell EF to generate this table with my column?
When a junction table in a many-to-many association should contain more information than just the two foreign keys, it's no longer possible to map the association as a 'pure' many-to-many (with hidden junction class).
You need an explicit class in the class model to address the extra information (as you already found out), but this also changes the association into 1-n-1:
class Document
{
...
public virtual ICollection<ProfileDocument> ProfileDocuments { get; set; }
}
class Profile
{
...
public virtual ICollection<ProfileDocument> ProfileDocuments { get; set; }
}
I'm new to mvc. I've creted an MVC app, in which i have used code first approach. Right now i have two tables Deal and Comment. Now i want to add a new table Category in the database and new column categoryId in Deal table.
How i can update database and model?
I'm using Sql Server 2008 R2 for Database.
I've following structure of class:
namespace FBWebApp.Models
{
public class Deal
{
public int ID { get; set; } // ID
public string Title { get; set; } // Titolo del deal
public string Description { get; set; } // Descrizione dell'annuncio
public string FacebookUID { get; set; } // UID facebook dell'utente
public string Visibility { get; set; } // Visibility
public string Category { get; set; }
public int Option1 { get; set; }
public int Option2 { get; set; }
public int Option3 { get; set; }
public int Option4 { get; set; }
public string PhotoURL { get; set; } // URL of the facebook photo profile
public string Name { get; set; } // Name of the user
public string ProfileUrl { get; set; } // URL of the facebook profile
public string Photo1 { get; set; } // URL of the Photo1 (local )
public string Photo2 { get; set; }
public string Photo3 { get; set; }
public string Photo4 { get; set; }
public string Photo5 { get; set; }
}
public class Comment
{
[Key]
public int CommentId { get; set; }
public string CommentText { get; set; }
public int ID { get; set; }
[ForeignKey("ID")]
public Deal DelNav { get; set; }
}
public class DealDBContext : DbContext
{
public DealDBContext() : base("DealDBContext") { }
public DbSet<Deal> Deals { get; set; }
public DbSet<Comment> Comments { get; set; }
}
}
Try using 'update-database -force -verbose' in the Package Manager Console.
If it doesn't work, modify the migration but typing 'add-migration somename' and it will apear in the Migrations folder.
If you are new to MVC and EF, definitely check out this tutorial. It explains all about that and everything else you need to know:
http://pluralsight.com/training/Player?author=scott-allen&name=mvc4-building-m1-intro&mode=live&clip=0&course=mvc4-building
first add your model :
public class Category
{
public int ID { get; set; }
public int cateName { get; set; }
}
in Deal class :
public class Deal
{
//..
[ForeignKey("CatId")]
public virtual Category Category { get; set; }
}
after Enable Migration you should use this command in console manager to update your database :
update-database
I have the following model:
public class Member
{
public int Id { get; set; }
public string Username { get; set; }
public int MainEmailId { get; set; }
public virtual Email MainEmail { get; set; }
public virtual ICollection<Email> MemberEmails { get; set; }
}
public partial class Email
{
public Int32 Id { get; set; }
public String Email { get; set; }
public int MemberId { get; set; }
public virtual Member Member { get; set; }
}
As you can see I wish to create a:
one-to-one relation from the Member to MemberEmail (the main email address)
one-to-many relation from Member to MemberEmail
I know how to do this with Code First Fluent API. However I need to do it with DataAnnotations only. Is this possible?
Thanks a lot.
How do I model the following using Castle ActiveRecord?
I have two classes, Customer and Task.
I would like to reuse a third class, Note, stored in a Collection in each of the Customer and Task classes.
public class Note
{
public int ID { get; set; }
public string Subject { get; set; }
public string Body { get; set; }
}
public class Customer
{
public int ID { get; set; }
public IList<Note> Notes { get; set; }
}
public class Task
{
public int ID { get; set; }
public IList<Note> Notes { get; set; }
}
I would then like to be able to pass the Notes collection to a Gridview, Listview or Repeater in the relevant ASP.Net page for the Customer or Task classes.
I think what you need is to implement a type hierarchy. You can read about it here.
We settled on the following pattern:
[ActiveRecord]
public class Note
{
[PrimaryKey]
public int ID { get; set; }
[Property]
public string Subject { get; set; }
[Property]
public string Body { get; set; }
[BelongsTo]
public Customer Customer { get; set; }
[BelongsTo]
public Customer Task{ get; set; }
}
[ActiveRecord]
public class Customer
{
[PrimaryKey]
public int ID { get; set; }
[HasMany]
public IList<Note> Notes { get; set; }
}
[ActiveRecord]
public class Task
{
[PrimaryKey]
public int ID { get; set; }
[HasMany]
public IList<Note> Notes { get; set; }
}