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TimelineMarker Class

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Represents metadata associated with a specific point in a media file.

Inheritance Hierarchy

System.Object
  System.Windows.DependencyObject
    System.Windows.Media.TimelineMarker

Namespace:  System.Windows.Media
Assembly:  System.Windows (in System.Windows.dll)

Syntax

'Declaration
Public NotInheritable Class TimelineMarker _
    Inherits DependencyObject
public sealed class TimelineMarker : DependencyObject

The TimelineMarker type exposes the following members.

Constructors

  Name Description
Public methodSupported by Silverlight for Windows Phone TimelineMarker Initializes a new instance of the TimelineMarker class.

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Properties

  Name Description
Public propertySupported by Silverlight for Windows Phone Dispatcher Gets the Dispatcher this object is associated with. (Inherited from DependencyObject.)
Public propertySupported by Silverlight for Windows Phone Text Gets or sets the text value of a TimelineMarker.
Public propertySupported by Silverlight for Windows Phone Time Gets or sets the time at which a TimelineMarker is reached.
Public propertySupported by Silverlight for Windows Phone Type Gets or sets the marker type of a TimelineMarker.

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Methods

  Name Description
Public methodSupported by Silverlight for Windows Phone CheckAccess Determines whether the calling thread has access to this object. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone ClearValue Clears the local value of a dependency property. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodSupported by Silverlight for Windows Phone Finalize Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetAnimationBaseValue Returns any base value established for a Silverlight dependency property, which would apply in cases where an animation is not active. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetType Gets the Type of the current instance. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetValue Returns the current effective value of a dependency property from a DependencyObject. (Inherited from DependencyObject.)
Protected methodSupported by Silverlight for Windows Phone MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone ReadLocalValue Returns the local value of a dependency property, if a local value is set. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone SetValue Sets the local value of a dependency property on a DependencyObject. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone ToString Returns a string that represents the current object. (Inherited from Object.)

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Fields

  Name Description
Public fieldStatic memberSupported by Silverlight for Windows Phone TextProperty Identifies the Text dependency property.
Public fieldStatic memberSupported by Silverlight for Windows Phone TimeProperty Identifies the Time dependency property.
Public fieldStatic memberSupported by Silverlight for Windows Phone TypeProperty Identifies the Type dependency property.

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Remarks

A timeline marker is metadata associated with a particular point in a media file. These markers are usually created ahead of time and stored in the media file itself. They are typically used to name different scenes in a video or provide scripting cues. By handling the MediaElement object's MarkerReached event or by accessing the MediaElement object's Markers property, you can use timeline markers to trigger actions or enable users to seek to selected positions in the media file.

TimelineMarker objects are used to represent all types of Windows Media technology timeline markers: markers and script commands (both metadata and separate stream). The following table lists how the Text and Type properties map to their source marker or script command.

TimelineMarker property

Windows Media marker

Windows Media script command

Text

"Name" field

"Param" field

Type

Always set to Name

"Type" field

The following example creates a MediaElement object and responds to its MarkerReached event. Each time a timeline marker is reached, the example displays the timeline marker's Time, Type, and Text values.

Run this sample

<StackPanel Margin="40">
  <StackPanel Orientation="Horizontal">
    <TextBlock FontSize="12" Foreground="DarkGray">Time:</TextBlock>
      <TextBlock x:Name="timeTextBlock" FontSize="12" />   
  </StackPanel>
  <StackPanel Orientation="Horizontal">
    <TextBlock FontSize="12" Foreground="DarkGray">Type:</TextBlock>
    <TextBlock x:Name="typeTextBlock" FontSize="12" />
  </StackPanel>
  <StackPanel Orientation="Horizontal">
    <TextBlock FontSize="12" Foreground="DarkGray">Value:</TextBlock>
    <TextBlock x:Name="valueTextBlock" FontSize="12" />
  </StackPanel>

  <!-- The MediaElement has the MarkerReached event attached. -->
  <MediaElement MarkerReached="OnMarkerReached" HorizontalAlignment="Left"
   Source="thebutterflyandthebear.wmv" Width="300" Height="200" />

</StackPanel>
Private Sub OnMarkerReached(ByVal sender As Object, ByVal e As TimelineMarkerRoutedEventArgs)
    timeTextBlock.Text = e.Marker.Time.Seconds.ToString
    typeTextBlock.Text = e.Marker.Type.ToString
    valueTextBlock.Text = e.Marker.Text.ToString
End Sub
private void OnMarkerReached(object sender, TimelineMarkerRoutedEventArgs e)
{
    timeTextBlock.Text = e.Marker.Time.Seconds.ToString();
    typeTextBlock.Text = e.Marker.Type.ToString();
    valueTextBlock.Text = e.Marker.Text.ToString();
}

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Thread Safety

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