Selection
- 2 minutes to read
The ASPxTreeList allows users to select (or clear) a node’s check box to select (or deselect) the corresponding node.
Set the Enabled property to true
to display the node check boxes. Set the AllowSelectAll property to true
to display a check box in the column header panel that selects/deselects all nodes.
<dx:ASPxTreeList ID="treeList" runat="server" DataSourceID="DepartmentsDataSource" KeyFieldName="ID">
<SettingsSelection Enabled="True" AllowSelectAll="True"/>
<!-- ... -->
Set a node’s AllowSelect property to false
to hide the node’s check box and prevent the node from being selected.
The example below shows how to prevent users from selecting a node that has no child nodes.
TreeListNodeIterator iterator = treeList.CreateNodeIterator();
TreeListNode node;
while (true) {
node = iterator.GetNext();
if (node == null) break;
node.AllowSelect = node.HasChildren;
}
Refer to the following section for the complete example: How to: Select Nodes That Meet the Specified Criteria.
Recursive Selection
Set the Recursive property to true
to make recursive selection available.
<dx:ASPxTreeList ID="treeList" runat="server" DataSourceID="DepartmentsDataSource" KeyFieldName="ID">
<SettingsSelection Enabled="True" Recursive="True"/>
<!-- ... -->
When recursive selection is available for users:
A parent node is automatically selected when all its child nodes are selected. Deselecting a child node automatically deselects its parent node(s).
When a user selects a parent node, its child nodes are automatically selected - including child nodes that are hidden with a filter.
A node that has selected and unselected child nodes is displayed with a grayed check box.
Refer to the following section for the complete example: How to: Enable Recursive Selection When Binding at Runtime.