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TextChangedEventArgs Class

Definition

Provides data for the TextChanged event.

public ref class TextChangedEventArgs : System::Windows::RoutedEventArgs
public class TextChangedEventArgs : System.Windows.RoutedEventArgs
type TextChangedEventArgs = class
    inherit RoutedEventArgs
Public Class TextChangedEventArgs
Inherits RoutedEventArgs
Inheritance
TextChangedEventArgs

Examples

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"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"    
  x:Class="SDKSample.DetectChangedTextExample"
  Title="DetectChangedText">
  <StackPanel>
    <TextBox
      Name="tbCountingChanges"    
      TextChanged="textChangedEventHandler"
      TextWrapping="Wrap">
      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>
    <TextBox Name="tbCounterText">0</TextBox>
    
  </StackPanel>  
</Page>

Below is the code behind for the example.

using System.Windows.Controls;

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)
        {

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

Namespace SDKSample

    Partial Public Class DetectChangedTextExample
        Inherits Page

        ' This is a counter for the number of times the TextChanged fires
        ' for the tbCountingChanges TextBox.
        Private uiChanges As Integer = 0

        ' Event handler for TextChanged Event.
        Private Sub textChangedEventHandler(ByVal sender As Object,
                                            ByVal args As TextChangedEventArgs)

            uiChanges += 1
            If tbCounterText IsNot Nothing Then
                tbCounterText.Text = uiChanges.ToString()
            End If

        End Sub
    End Class
End Namespace

Constructors

TextChangedEventArgs(RoutedEvent, UndoAction, ICollection<TextChange>)

Initializes a new instance of the TextChangedEventArgs class, using the specified event ID, undo action, and text changes.

TextChangedEventArgs(RoutedEvent, UndoAction)

Initializes a new instance of the TextChangedEventArgs class, using the specified event ID and undo action.

Properties

Changes

Gets a collection of objects that contains information about the changes that occurred.

Handled

Gets or sets a value that indicates the present state of the event handling for a routed event as it travels the route.

(Inherited from RoutedEventArgs)
OriginalSource

Gets the original reporting source as determined by pure hit testing, before any possible Source adjustment by a parent class.

(Inherited from RoutedEventArgs)
RoutedEvent

Gets or sets the RoutedEvent associated with this RoutedEventArgs instance.

(Inherited from RoutedEventArgs)
Source

Gets or sets a reference to the object that raised the event.

(Inherited from RoutedEventArgs)
UndoAction

Gets how the undo stack is caused or affected by this text change.

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
InvokeEventHandler(Delegate, Object)

Performs the proper type casting to call the type-safe TextChangedEventHandler delegate for the TextChanged event.

MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
OnSetSource(Object)

When overridden in a derived class, provides a notification callback entry point whenever the value of the Source property of an instance changes.

(Inherited from RoutedEventArgs)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to