LINQ to Entities does not recognize the method 'System.String getFullname(System.String, System.String)'

Question

I'm trying to call a business model class static method from my controller action method but Im failling. Please I need really your helps. Thanks

public ActionResult Index()
{

 var model =
                           _db.members
                           .Include(m =>m.homeTownCity)
                           .Include(m => m.currentCity)
                           .OrderBy(m => m.fname)
                           .ThenBy(m => m.lname)
                           .Select(m => new MembersListViewModel
                           {
                               homeTown = m.homeTownCity.Name,
                               currentCity = m.currentCity.Name,

                               //Calling a business class static method
                               Name= MemberManagement.getFullname(m.lname,m.fname),
                               spoken = m.spoken,
                               hasPosted = m.posts.Count()
                           });


           return View(model);
}

 public class MemberManagement
 {
        public static string getFullname( string fname,string lname) {

            string fullname = fname + "  " + lname;
            return fullname;
        }
}

Answer 1

This is because your static method can not be converted to SQL and executed by entity framework.

Pull your members down first as a list and then do the select since that will be executed by the server rather than at the SQL level.

var members =
                           _db.members
                           .Include(m =>m.homeTownCity)
                           .Include(m => m.currentCity)
                           .OrderBy(m => m.fname)
                           .ThenBy(m => m.lname).ToList();


var model = members.Select(m => new MembersListViewModel
                           {
                               homeTown = m.homeTownCity.Name,
                               currentCity = m.currentCity.Name,

                               //Calling a business class static method
                               Name= MemberManagement.getFullname(m.lname,m.fname),
                               spoken = m.spoken,
                               hasPosted = m.posts.Count()
                           }).ToList();