WPF C#

    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Class="ThicknessConverter_Csharp.Window1"
    Title="ThicknessConverter Sample">
  
    
      ThicknessConverter Sample
    
      
        
          
          
        

        
        
      
    
    
      
        
        
        
      

      
        
        
        
        
      

      Change the BorderThickness Property:
      
        0
        5
        10
        15
        20
        25
        30
        35
        40
        45
        50
      
    
          

//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();
        }
  }
}