The ASPxTreeList control stores its columns within the ASPxTreeList.Columns collection. To access only visible columns, use the ASPxTreeList.VisibleColumns property. Individual columns are represented by the TreeListDataColumn objects. A data column can be accessed by specifying its ID, caption or the name of the data source field to which it is bound.
using DevExpress.Web.ASPxTreeList; // Accessing a column by specifying the name of the data source field to which it is bound. TreeListDataColumn colDepartment = treeList.Columns["Department"] as TreeListDataColumn; // Accessing a column by specifying its caption. TreeListDataColumn colPhone = treeList.Columns["Primary Phone"] as TreeListDataColumn; // Accessing a column by its index within the Columns collection. TreeListDataColumn colFirstColumn = treeList.Columns as TreeListDataColumn;
On the client, data columns can be accessed via the methods listed below:
The number of columns can be obtained via the ASPxClientTreeList.GetColumnCount method.