Load Grid from stored proc using entity framework

[tcl4p]

I'm trying to load a grid control with data from a stored procedure using entity framework and I'm getting the following error: " The ObjectContext instance has been disposed and can no longer be used for operations that require a connection".    I had been using the commented out code below, which works, but wanted to use Entity Framework to call the stored procedure.  I've tried the code with and without the databind() without any difference.  the code for one of the stored procedures.  I have several other calls to stored proc's, which are called to Entity Framework that work fine, but they return distinct data values.  Any help appreciated.

Tom

 {                  // Working code commented out  below 
                    //if (ViewMode == "Department")
                    //{
                    //    this.grdDutyCrew.DataSource = clsDept.GetAvailabilityDutyCrewByViewMode(clsDept.DeptID, StationID, Convert.ToDateTime(SelectedDate));
                    //}
                    //else
                    //{
                    //    this.grdDutyCrew.DataSource = clsDept.GetDutyCrewByDate(StationID, Convert.ToDateTime(SelectedDate));
                    //}
// Entity Framework Call:
                    using (var context = new sfhsEntities())
                    {
                        if (context.DatabaseExists())
                        {
                            if (ViewMode == "Department")
                            {
                                this.grdDutyCrew.DataSource = context.GetAvailabilityDutyCrewByViewMode(clsDept.DeptID, StationID, SelectedDate);
                            }
                            else
                            {
                                this.grdDutyCrew.DataSource = context.GetDutyCrewByDate(StationID, SelectedDate);
                            }
                        }
                        this.grdDutyCrew.DataBind();
                    }
                }
//One of the Called Stored Procedure:
  public DataSet GetDutyCrewByDate(int StationID, DateTime SelectedDate)
    {
        SqlDataAdapter da = new SqlDataAdapter();
        DataSet ds = new DataSet();
        if (Conn.ObjConn.State == ConnectionState.Connecting)
        {
            return null;
        }

        if (Conn.ObjConn.State != ConnectionState.Open)
        {
            Conn.GetConnection();
        }
        SqlCommand cmd = Conn.ObjConn.CreateCommand();
        cmd.CommandType = CommandType.StoredProcedure;
        cmd.CommandText = "GetDutyCrewByDate";
        cmd.Parameters.Add("@rc", SqlDbType.Int).Direction = ParameterDirection.ReturnValue;
        cmd.Parameters.Add("@StationID", SqlDbType.Int).Value = StationID;
        cmd.Parameters.Add("@SelectedDate", SqlDbType.DateTime).Value = SelectedDate;

        try
        {
            da.SelectCommand = cmd;
            da.Fill(ds);
             return ds;
        }
        catch (Exception ex)
        {
            ErrMsg = ex.Message;
            return null;
        }
        finally
        {
            if (Conn.ObjConn != null)
            {
                ((IDisposable)Conn.ObjConn).Dispose();
            }
        }
    }

[Konstantin Dikov]

Hello Tom,

This is not related to RadGrid in any way and is a general Entity Framework related issue, so I could suggest that you take a look at the following forum threads, where some details on the matter could be found:

• How to solve the error The ObjectContext instance has been disposed and can no longer be used for operations that require a connection 
• error:The ObjectContext instance has been disposed and can no longer be used for operations that require a connection

Hope this helps.


Regards,
Konstantin Dikov
Telerik