WPFで動画ファイルを再生するサンプル「イベントの動作確認」

<Window x:Class="MediaElementSample.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:MediaElementSample"
        mc:Ignorable="d"
        Title="MainWindow" Height="600" Width="800">
    <Window.Resources>
        <Style x:Key="ButtonStyle" TargetType="Button">
            <Setter Property="Margin" Value="10"/>
            <Setter Property="Width" Value="100"/>
            <Setter Property="Height" Value="30"/>
        </Style>
    </Window.Resources>
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="*"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>

        <MediaElement
            Grid.Row="0"
            x:Name="MovieControl"
            LoadedBehavior="Manual"
            UnloadedBehavior="Stop"            
            BufferingEnded="BufferingEndedEvent"            
            BufferingStarted="BufferingStartedEvent"
            MediaOpened="MediaOpenedEvent"
            MediaEnded="MediaEndedEvent"
            MediaFailed="MediaFailedEvent"
            ScriptCommand="ScriptCommandEvent">
        </MediaElement>

        <StackPanel
            Grid.Row="1" 
            Orientation="Horizontal"
            HorizontalAlignment="Center">
            <Button
                x:Name="FileSelectButton"
                Style="{StaticResource ButtonStyle}" 
                Click="FileSelect">
                ファイル選択
            </Button>
            <Button
                x:Name="PlayButton"
                Style="{StaticResource ButtonStyle}" 
                Click="PlayClick">
                再生
            </Button>
            <Button
                x:Name="PauseButton"
                Style="{StaticResource ButtonStyle}" 
                Click="PauseClick">
                一時停止
            </Button>
            <Button
                x:Name="StopButton"
                Style="{StaticResource ButtonStyle}" 
                Click="StopClick">
                停止
            </Button>
        </StackPanel>
    </Grid></Window>

using System.Diagnostics;
using System.Windows;
using Microsoft.Win32;

namespace MediaElementSample;

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
    }
    public void FileSelect(object sender, EventArgs e)
    {
        var d =new OpenFileDialog();
        if (d.ShowDialog() == false) return;
        this.Title = d.FileName;
        MovieControl.Source = new Uri(d.FileName);
    }
    public void PlayClick(object sender, EventArgs e)
    {
        if (MovieControl.Source is null) return;
        MovieControl.Play();
    }
    public void PauseClick(object sender, EventArgs e)
    {
        if (MovieControl.Source is null) return;
        MovieControl.Pause();
    }
    public void StopClick(object sender, EventArgs e)
    {
        if (MovieControl.Source is null) return;
        MovieControl.Stop();
    }
    public void BufferingEndedEvent(object sender, EventArgs e)
    {
        Debug.Print("BufferingEnded イベント発生");
    }
    public void BufferingStartedEvent(object sender, EventArgs e)
    {
        Debug.Print("BufferingStarted イベント発生");
    }
    public void MediaOpenedEvent(object sender, EventArgs e)
    {
        Debug.Print("MediaOpened イベント発生");
    }
    public void MediaEndedEvent(object sender, EventArgs e)
    {
        Debug.Print("MediaEnded イベント発生");
    }
    public void MediaFailedEvent(object sender, EventArgs e)
    {
        Debug.Print("MediaFailed イベント発生");
    }
    public void ScriptCommandEvent(object sender, EventArgs e)
    {
        Debug.Print("ScriptCommand イベント発生");
    }
}