Entity framework join 2 tables - entity-framework

Question

Beginner with entity framework and mvc here.
I have 2 table models:
UserProfile
[Table("UserProfile")]
public class UserProfile
{
[Key]
[DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
public int UserId { get; set; }
public string UserName { get; set; }
public string Email { get; set; }
}
and
ChatLogs
[Table("ChatLogs")]
public class ChatLogs
{
[Key]
[DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
public int ChatLogId { get; set; }
[Column("Message")]
public string Message { get; set; }
[Column("UserId")]
public int UserId { get; set; }
public override string ToString()
{
return "Person: " + Message + " " + UserId;
}
}
UserId in table ChatLogs is foreign key to UserPorfile UserId primary key.
I am trying to join these 2 tables in Asp.NET MVC 4
Tested SQL query:
select * from UserProfile as a join ChatLogs as b on a.UserId = b.UserId
Tested Linq query:
from b in db.ChatLogs
select new {
ChatLogId = b.ChatLogId,
Message = b.Message,
UserId = b.UserId,
Column1 = (int?)b.UserProfile.UserId,
UserName = b.UserProfile.UserName,
Email = b.UserProfile.Email
}
I am using software called "Linqer" for learning purposes. It conversts SQL to Linq.
ActionResult code:
private ChatLogContext db = new ChatLogContext();
public ActionResult Index()
{
var list = from b in db.ChatLogs
select new
{
ChatLogId = b.ChatLogId,
Message = b.Message,
UserId = b.UserId,
Column1 = (int?)b.UserProfile.UserId,
UserName = b.UserProfile.UserName,
Email = b.UserProfile.Email
};
var vm = new ChatLogsViewModel { LogListString = string.Join("\n", list) };
return View(vm);
}
ChatLogViewModel has only a string variable for printing list in view.
But I get an error:
'Chat.Models.ChatLogs' does not contain a definition for 'UserProfile' and no extension method 'UserProfile' accepting a first argument of type 'Chat.Models.ChatLogs' could be found (are you missing a using directive or an assembly reference?)
So do I have to connect those 2 entities somehow so they would know about each other?

Answer 1

Try this:
[Table("UserProfile")]
public class UserProfile
{
[Key]
[DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
public int UserId { get; set; }
public string UserName { get; set; }
public string Email { get; set; }
**public virtual ICollection<ChatLogs> ChatLogs { get; set; }**
}
[Table("ChatLogs")]
public class ChatLogs
{
[Key]
[DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
public int ChatLogId { get; set; }
[Column("Message")]
public string Message { get; set; }
[Column("UserId")]
public int UserId { get; set; }
**public virtual UserProfile UserProfile { get;set; }**
public override string ToString()
{
return "Person: " + Message + " " + UserId;
}
}

Answer 2

The easiest way to connect is to make Chatlogs available on the user as a List:
[Table("UserProfile")]
public class UserProfile
{
[Key]
[DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
public int UserId { get; set; }
public string UserName { get; set; }
public string Email { get; set; }
public List<ChatLog> ChatLogs{ get; set;}
}
Now you can do the following:
var users = Users.Include("ChatLogs");
Every user will now have its list of ChatLogs filled in correctly.