BeforeExpandEventArgs Class

Provides data for the TreeList.BeforeExpand event.

Namespace: DevExpress.XtraTreeList

Assembly: DevExpress.XtraTreeList.v18.1.dll

Declaration

C#

public class BeforeExpandEventArgs :
    NodeEventArgs

VB.NET

Public Class BeforeExpandEventArgs
    Inherits NodeEventArgs

Related API Members

BeforeExpandEventArgs is the data class for the following events:

• TreeList.BeforeExpand

Remarks

The TreeList.BeforeExpand event occurs before Tree List node expansion.

The BeforeExpandEventArgs.CanExpand property value indicates whether a node can be expanded.

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the BeforeExpandEventArgs class.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

VB.NET

how-to-implement-the-cells-multi-selection-feature-in-treelist-e2795/VB/WindowsApplication1/Helper/BlockSelector.vb#L81

Private Sub fList_BeforeExpand(ByVal sender As Object, ByVal e As BeforeExpandEventArgs)
    fBlock.Clear()

how-to-use-datatable-with-master-detail-relationships-in-treelist-e3597/VB/E3597/UnboundMasterDetailTree.vb#L59

End Sub
Private Sub BeforeExpand(ByVal sender As Object, ByVal e As BeforeExpandEventArgs)
    If e.Node.Nodes.Count <> 0 Then

how-to-use-treelist-for-file-management-drag-and-drop-files-and-folders-e3400/VB/FileList/FileListHelper.vb#L128

Private Sub treeList1_BeforeExpand(ByVal sender As Object, ByVal e As DevExpress.XtraTreeList.BeforeExpandEventArgs)
    If e.Node.Tag IsNot Nothing Then

how-to-create-an-analog-of-gridlookupedit-with-treelist-in-a-popup-window-e4319/VB/Form1.vb#L165

Private Sub TreeList_BeforeExpand(ByVal sender As Object, ByVal e As BeforeExpandEventArgs)
    GenerateTestChildrenNodes(e.Node)

how-to-implement-node-dynamic-loading-in-unbound-mode-t500394/VB/TreeList-UnboundMode-ViaBeforeExpandEvent/Form1.vb#L136

Private Sub treeList1_BeforeExpand(ByVal sender As Object, ByVal e As DevExpress.XtraTreeList.BeforeExpandEventArgs)
    If e.Node.Tag IsNot Nothing Then

C#

how-to-use-datatable-with-master-detail-relationships-in-treelist-e3597/CS/E3597/UnboundMasterDetailTree.cs#L62

}
private void BeforeExpand(object sender, BeforeExpandEventArgs e)
{

how-to-use-treelist-for-file-management-drag-and-drop-files-and-folders-e3400/CS/FileList/FileListHelper.cs#L140

private void treeList1_BeforeExpand(object sender, DevExpress.XtraTreeList.BeforeExpandEventArgs e)
{

how-to-create-an-analog-of-gridlookupedit-with-treelist-in-a-popup-window-e4319/CS/Form1.cs#L168

void TreeList_BeforeExpand(object sender, BeforeExpandEventArgs e)
{

how-to-implement-node-dynamic-loading-in-unbound-mode-t500394/CS/TreeList-UnboundMode-ViaBeforeExpandEvent/Form1.cs#L133

private void treeList1_BeforeExpand(object sender, DevExpress.XtraTreeList.BeforeExpandEventArgs e) {
    if (e.Node.Tag != null) {

Inheritance

Object

EventArgs

NodeEventArgs

BeforeExpandEventArgs