<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" x:Class="ThicknessConverter_Csharp.Window1" Title="ThicknessConverter Sample"> <DockPanel Width="400" HorizontalAlignment="Left" VerticalAlignment="Top"> <TextBlock DockPanel.Dock="Top" FontFamily="Verdana" FontSize="18" FontWeight="Bold" Margin="5"> ThicknessConverter Sample</TextBlock> <Border Name="border1" Height="300" Width="300" Border.BorderThickness="2" Border.BorderBrush="Black" DockPanel.Dock="Top"> <Grid Height="30" VerticalAlignment="Top"> <Grid.RowDefinitions> <RowDefinition/> <RowDefinition/> </Grid.RowDefinitions> <TextBlock Grid.Row="0" Name="bThickness"/> <TextBlock Grid.Row="1" Name="bColor"/> </Grid> </Border> <Grid DockPanel.Dock="Top"> <Grid.RowDefinitions> <RowDefinition/> <RowDefinition/> <RowDefinition/> </Grid.RowDefinitions> <Grid.ColumnDefinitions> <ColumnDefinition/> <ColumnDefinition/> <ColumnDefinition/> <ColumnDefinition/> </Grid.ColumnDefinitions> <TextBlock Grid.Row="1" Grid.Column="0" Margin="10,0,0,0" TextWrapping="Wrap">Change the BorderThickness Property:</TextBlock> <ListBox VerticalAlignment="Top" Grid.Column="1" Grid.Row="1" Width="50" Height="50" Margin="5" SelectionChanged="changeThickness"> <ListBoxItem>0</ListBoxItem> <ListBoxItem>5</ListBoxItem> <ListBoxItem>10</ListBoxItem> <ListBoxItem>15</ListBoxItem> <ListBoxItem>20</ListBoxItem> <ListBoxItem>25</ListBoxItem> <ListBoxItem>30</ListBoxItem> <ListBoxItem>35</ListBoxItem> <ListBoxItem>40</ListBoxItem> <ListBoxItem>45</ListBoxItem> <ListBoxItem>50</ListBoxItem> </ListBox> </Grid> </DockPanel> </Window> //File:Window.xaml.cs using System; using System.Windows; using System.Windows.Controls; using System.Windows.Documents; using System.Windows.Navigation; using System.Windows.Media; namespace ThicknessConverter_Csharp { public partial class Window1 : Window { public void changeThickness(object sender, SelectionChangedEventArgs args) { ListBoxItem li = ((sender as ListBox).SelectedItem as ListBoxItem); ThicknessConverter myThicknessConverter = new ThicknessConverter(); Thickness th1 = (Thickness)myThicknessConverter.ConvertFromString(li.Content.ToString()); border1.BorderThickness = th1; bThickness.Text = "Border.BorderThickness =" + li.Content.ToString(); } } }