Fill by default Select = null in linq

Question

I have this sentence linq, with select inside a select using a two viewmodels, the problem is that in my loginviewmodel not all have a status equal to received, there may be nulls, but when putting them in my view some columns in my grid appear empty, I would like to see N/A appear by default if logviewmodel is = null but I don't know how to do it, I return this as JSON since I'm using datatable on the server side, I don't know if manipulating the json can also be done

I Share my linq sentence

  var result = db.document.Select(d => new DocumentViewModel
  {
       DocumentId = d.DocumentId,
       Name = w.name
       ReceivedLogs = d.Logs
      .Where(l => l.Status == Status.Received)
      .Select(l => new LogViewModel
      {
         CurrentApprover = l.User,
         NameApprover = l.User.FullName
      }).FirstOrDefault()
      }).ToList();

thanks

Answer 1

You can check if FirstOrDefault() returns null and then use a default LogViewModel:

     var result = db.document.Select(d => new DocumentViewModel
     {
       DocumentId = d.DocumentId,
       Name = w.name
       ReceivedLogs = d.Logs
            .Where(l => l.Status == Status.Received)
            .Select(l => new LogViewModel
            {
               CurrentApprover = l.User,
               NameApprover = l.User.FullName
            }).FirstOrDefault() ?? new LogViewModel {
                                          CurrentApprover = "N/A",
                                          NameApprover = "N/A" 
                                       }
      }).ToList();