GridDropDownColumn setting DataSource separately

[Nicolas]

Hi

I'm trying to make a RadGrid with cascadingcombo boxes. I'm new to Telerik so i have no clue what i'm doing at the moment. I tried to make the DropDown colum his datasource a list that i get from the DB trough Linq and trough a DTOmapper. So the thing is i can't attach my list of dto's to the comboboxcolum ! Because it only takes a string and not a List of objects. Does anyone know what i'm doing wrong or am i completly forgetting something ?

Ill attach my code

private void LoadBehandelaars(int toInt32)
     {
         DataTable behandelaar = new DataTable();
         List<User> Behandelaars = _clientenFunctions.GetBehandelaarsByDiscipline(Convert.ToInt32(Session["cate"]));
         behandelaar.PrimaryKey = new DataColumn[]{ behandelaar.Columns.Add("NestorNummer",typeof(string))};
         behandelaar.Columns.Add("UserName", typeof (string));

         foreach (User user in Behandelaars)
         {
             behandelaar.Rows.Add(new object[]
                                      {
                                          user.NestorNummer, user.UserName
                                      }
                 );
         }

         GridDropDownColumn BehanderlaarColumn = new GridDropDownColumn();
         BehanderlaarColumn.HeaderText = "Behandelaar";
         BehanderlaarColumn.DataSourceID = behandelaar.ToString();
     }

[Kostadin]

Hi Nicolas,

The built-in GridDropDownColumn is designed to be used mainly with DataTables in order to easily map and generate their dropdown items values in conjunction with the DataField/ListValueField/DataSourceID/ListDataMember values of the column. For custom objects collections consider replacing the GridDropDownColumn with template column holding RadComboBox in its edit template (generating/binding the items for the RadComboBox inside the ItemDataBound handler of RadGrid).
Check this demo which demonstrates how to implement RadComboBox into GridTemplateColumn.

Greetings,
Kostadin
the Telerik team

[K]

If I have a response object that I am converting into tables.  Part of that response object contains tables that are use to populate GridDropDownColumns.  The table creation happens in the code-behind.  How do I link the GridDrownDownColumn's data source to the table that was created in the code-behing.  The datasourceid is specified in the ASPX.  Is there a way to do that?  It is almost like I need to "Bind" event for the GridDropDownColumn.

[Kostadin]

Hello,

I am afraid for such scenario you have to use a TemplateColumn with RadComboBox as and EditTemplate. The provided demo from my previous reply will help you figure out how you can achieve that.

Regards,
Kostadin
Telerik