Search for an element by using Panel.FindName()
<StackPanel Name="root" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" x:Class="WpfApplication1.FEFindName"> <StackPanel.Resources> <Style TargetType="{x:Type Button}"> <Setter Property="Height" Value="20"/> <Setter Property="Width" Value="250"/> <Setter Property="HorizontalAlignment" Value="Left"/> </Style> <Style TargetType="{x:Type TextBlock}"> <Setter Property="HorizontalAlignment" Value="Left"/> <Setter Property="FontSize" Value="20"/> </Style> </StackPanel.Resources> <Button Click="Find">Find element with the ID "dog" and change color</Button> <StackPanel Name="stackPanel"> <TextBlock Name="cat">Cat</TextBlock> <TextBlock Name="dog">Dog</TextBlock> <TextBlock Name="fish">Fish</TextBlock> </StackPanel> </StackPanel> //File:Window.xaml.vb Imports System Imports System.Windows Imports System.Windows.Controls Imports System.Windows.Media Namespace WpfApplication1 Public Partial Class FEFindName Private Sub Find(sender As Object, e As RoutedEventArgs) Dim wantedNode As Object = stackPanel.FindName("dog") If TypeOf wantedNode Is TextBlock Then Dim wantedChild As TextBlock = TryCast(wantedNode, TextBlock) wantedChild.Foreground = Brushes.Blue End If End Sub End Class End Namespace