' To support basic filtering, the employees cannot
' be returned as an array of objects, rather as a
' DataSet of the raw data values.
Public Shared Function GetAllEmployeesAsDataSet() As DataSet
   Dim employees As ICollection = GetAllEmployees()

   Dim ds As New DataSet("Table")

   ' Create the schema of the DataTable.
   Dim dt As New DataTable()
   Dim dc As DataColumn
   dc = New DataColumn("FirstName", GetType(String))
   dt.Columns.Add(dc)
   dc = New DataColumn("LastName", GetType(String))
   dt.Columns.Add(dc)
   dc = New DataColumn("Title", GetType(String))
   dt.Columns.Add(dc)
   dc = New DataColumn("Courtesy", GetType(String))
   dt.Columns.Add(dc)
   dc = New DataColumn("Supervisor", GetType(Int32))
   dt.Columns.Add(dc)

   ' Add rows to the DataTable.
   Dim emplEnum As IEnumerator = employees.GetEnumerator()
   Dim row As DataRow
   Dim ne As NorthwindEmployee
   While emplEnum.MoveNext()
      ne = CType(emplEnum.Current, NorthwindEmployee)
      row = dt.NewRow()
      row("FirstName") = ne.FirstName
      row("LastName") = ne.LastName
      row("Title") = ne.Title
      row("Courtesy") = ne.Courtesy
      row("Supervisor") = ne.Supervisor
      dt.Rows.Add(row)
   End While
   ' Add the complete DataTable to the DataSet.
   ds.Tables.Add(dt)

   Return ds
End Function 'GetAllEmployeesAsDataSet