TextChangedEventArgs Class

Provides data for the TextChanged event.

Namespace: System.Windows.Controls
Assembly: PresentationFramework (in presentationframework.dll)
XML Namespace:  http://schemas.microsoft.com/winfx/2006/xaml/presentation

public class TextChangedEventArgs : RoutedEventArgs
public class TextChangedEventArgs extends RoutedEventArgs
public class TextChangedEventArgs extends RoutedEventArgs
You cannot use this managed class in XAML.

The following example displays the number of times the text in a TextBox changes. Below is the XAML code for the example.

<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
      Here is the initial text in the textbox.  Each time the contents of this box is changed, a change counter will
      be incremented and displayed in the TextBox below.  Note that the TextChanged event is called when the TextBox
      control is initially populated with text, so the changes counter starts of at 1.
    <TextBox Name="tbCounterText">0</TextBox>

Below is the code behind for the example.

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;

namespace SDKSample
    public partial class DetectChangedTextExample : Page

        // This is a counter for the number of times the TextChanged fires
        // for the tbCountingChanges TextBox.
        private int uiChanges = 0;

        // Event handler for TextChanged Event.
        private void textChangedEventHandler(object sender, TextChangedEventArgs args)

            if (tbCounterText != null)
                tbCounterText.Text = uiChanges.ToString();



Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0