TreeViewControl.Nodes Property

Gets the collection of root nodes.

Assembly : DevExpress.Xpf.Grid.v25.2.dll

NuGet Package : DevExpress.Wpf.Grid.Core

Declaration

C#
VB.NET

csharp

public TreeListNodeCollection Nodes { get; }

Public ReadOnly Property Nodes As TreeListNodeCollection

Property Value

Type	Description
TreeListNodeCollection

The collection of root nodes.

Remarks

You can use the Nodes property to create an unbound tree without a data source:

XAML

xaml

<dxg:TreeViewControl AutoExpandAllNodes="True">
    <dxg:TreeViewControl.Nodes>
        <dxg:TreeListNode Content="Root Node 1">
            <dxg:TreeListNode.Nodes>
                <dxg:TreeListNode Content="Level 1">
                    <dxg:TreeListNode.Nodes>
                        <dxg:TreeListNode Content="Level 2"/>
                    </dxg:TreeListNode.Nodes>
                </dxg:TreeListNode>
            </dxg:TreeListNode.Nodes>
        </dxg:TreeListNode>
        <dxg:TreeListNode Content="Root Node 2">
            <dxg:TreeListNode.Nodes>
                <dxg:TreeListNode Content="Level 1"/>
            </dxg:TreeListNode.Nodes>
        </dxg:TreeListNode>
    </dxg:TreeViewControl.Nodes>
</dxg:TreeViewControl>

Specify the TreeViewFieldName property to display data in the TreeViewControl if you set an object as a node’s content.

Iterate Through Nodes

Create a new instance of the TreeListNodeIterator class to iterate through nodes. You can specify a start node or the collection of nodes, and whether to process only visible nodes.

Note

If you specified the collection of nodes, the Node Iterator starts to process nodes from the first node in the specified collection.

The following code sample iterates through all visible nodes to expand nodes that have more than three child nodes.

XAML

xaml

<dxg:TreeViewControl x:Name="treeview"
                     Loaded="treeview_Loaded"
                     ... />

C#
VB.NET

csharp

void SmartExpandNodes(int minChildCount) {
    foreach (DevExpress.Xpf.Grid.TreeListNode node in new DevExpress.Xpf.Grid.TreeListNodeIterator(treeview.Nodes, true)) {
        node.IsExpanded = node.Nodes.Count >= minChildCount;
    }
}
void treeview_Loaded(object sender, RoutedEventArgs e) {
    SmartExpandNodes(3);
}

Private Sub SmartExpandNodes(ByVal minChildCount As Integer)
    For Each node As DevExpress.Xpf.Grid.TreeListNode In New DevExpress.Xpf.Grid.TreeListNodeIterator(treeview.Nodes, True)
        node.IsExpanded = node.Nodes.Count >= minChildCount
    Next
End Sub

Private Sub treeview_Loaded(ByVal sender As Object, ByVal e As RoutedEventArgs)
    SmartExpandNodes(3)
End Sub