c# - Why am I not getting .CopyToDataTable() in Linq Query()

Question

This following code example is borrowed from MSDN here. I am not getting query.CopyToDataTable() available in my code. (see the commented line in my following code).

public static bool SetPhysicianAsNotonServer(DataTable dt)
        {
            DataTable dtPhysicianServer = dt;
            DataTable dtPhysicianClient = GetPhysicianClient();

            var query =
                from SPhysician in dtPhysicianServer.AsEnumerable()
                join CPhysician in dtPhysicianClient.AsEnumerable()
                on SPhysician.Field<string>("PhysicianNumber") equals
                    CPhysician.Field<string>("PhysicianNumber")
                select new
                {
                    PhysicianNumber = CPhysician.Field<string>("PhysicianNumber")
                 };

            DataTable FilterDt = query; //query.CopyToDataTable();
            //YET TO DO CODE HERE
            return true;
        }

Answer 1

Your select statement is returning a sequence of strings (IEnumerable<string> or IQueryable<string>), not a sequence of DataRows. CopyToDataTable() is only available on IEnumerable<T> where T is or derives from DataRow.

Instead of select new { ... } - which will just get you a new sequence of that type, try:

select CPhysician;

Which should return the desired sequence of CPhysician rows.

Edit If you wish to convert a non-datatable-derived T to a datatable, MSDN has a sample class that reflects out any type and performs the conversion.

http://msdn.microsoft.com/en-us/library/bb669096.aspx