HierarchicalCollection<T>.FindRecursive(Predicate<T>) Method

Returns the first element that matches the conditions defined by the specified predicate.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v18.2.dll

Declaration

C#

public T FindRecursive(
    Predicate<T> match
)

VB.NET

Public Function FindRecursive(
    match As Predicate(Of T)
) As T

Parameters

Name	Type	Description
match	Predicate<T>	A delegate that defines the conditions of the elements to search for.

Returns

Type	Description
T	The element that matches the conditions defined by the predicate.

Remarks

The FindRecursive method individually passes elements of the current hierarchical collection to a predicate, and returns the first element that matches the predicate. A predicate is a delegate to a method that returns true if the object passed to it matches the conditions defined in the delegate; otherwise the method returns false.

Example

The code sample below demonstrates how you can find and select a node by custom conditions using the FindRecursive method. In this sample, a node is searched by its url (or a part of url) that is entered in a text box.

C#

using DevExpress.Web.ASPxTreeView;
...
protected void btn_FindNode_Click(object sender, EventArgs e) {
     if (ASPxTextBox1.Text != "") {
          ASPxTreeView1.SelectedNode = ASPxTreeView1.Nodes.FindRecursive(FindInUrl);
     }
}
public bool FindInUrl(TreeViewNode node) {
     return node.NavigateUrl.Contains(ASPxTextBox1.Text);
}

VB.NET

Imports DevExpress.Web.ASPxTreeView
...
Protected Sub btn_FindNode_Click(ByVal sender As Object, ByVal e As EventArgs)
     If ASPxTextBox1.Text <> "" Then
          ASPxTreeView1.SelectedNode = ASPxTreeView1.Nodes.FindRecursive(AddressOf FindInUrl)
     End If
End Sub
Public Function FindInUrl(ByVal node As TreeViewNode) As Boolean
     Return node.NavigateUrl.Contains(ASPxTextBox1.Text)
End Function