Question

I have 2 tables:
Users: Id, UserName, …
Messages: Id, MsgText, IsRead,….

I want to select from these tables to that I get number of message per user.
For example i want to have the result in this format:
UserID 1 NumberOfMessages 10
UserID 2 NumberOfMessages 4
UserID 3 NumberOfMessages 0
….

How to write this in one linq statement.

Notes: I am using codefirst entity framework, and using linq methods format.

public partial class User
    {
        public long Id { get; set; }
        public string FullName { get; set; }
        public string UserName { get; set; }

         public virtual ICollection<Message> Messages { get; set; }
     }

     public partial class Message
    {
        public long Id { get; set; }
        public long SenderId { get; set; }
        public long ReceiverId { get; set; }
        public string MessageText { get; set; }
        public System.DateTime CreatedOn { get; set; }

        public virtual User Sender { get; set; }
        public virtual User Receiver { get; set; }
    }

Answer 1

var result = dbContext.Users
    .Select(u => new 
                   {
                       UserID = u.Id, 
                       NumberOfMessages = u.Messages.Count()
                   })
    .ToList();