Play Video in WPF

If you have built any video-enabled application prior to WPF, you must be familiar with the Windows Media Player ActiveX control. The WPF library provides the MediaElement control that encapsulates the Windows Media Player functionality.

The MediaElement tag in XAML allows you to play videos in XAML and WPF. The Source attribute of the tag takes the full path of the video. The following code snippet uses the MediaElement to display a video.

<MediaElementName="VideoControl"Width="200"Height ="400"
                  Source="C:\Windows\System32\oobe\images\intro.wmv" >
</MediaElement>

The file can also be an MPEG. The following code snippet plays a MPEG video.

<MediaElementName="VideoControl"Width="200"Height ="400"
                  Source="C:\TestV.MPG" >
</MediaElement> 

The Width and Height attributes sets the width and height of the control respectively.

Setting MediaElement Properties Dynamically

You can also access the control programmatically and set its properties in your code. The following code snippet sets the MediaControls properties at run-time.

VideoControl.Volume = 100;

VideoControl.Width = 440;

VideoControl.Height = 280;

The Application

Now let's build our video application. I want to create an application that looks like Figure 1. As you can see from this figure, the Browse button allows me to browse a video file and Play, Pause, and Stop buttons plays, pauses, and stops the video.

Figure 1. Video enabled WPF application

The code listed in Listing 1 creates the user interface screen.

<TextBoxHeight="20"Margin="10,7,134,0"Name="MediaPathTextBox"VerticalAlignment="Top"  ></TextBox>
    <ButtonHeight="20"HorizontalAlignment="Right"Margin="0,6,14,0"Name="BrowseButton"
            VerticalAlignment="Top"Width="94"Click="BrowseClick">
        Browse Media
    </Button>
    <MediaElementCanvas.Left="20"Canvas.Top ="40"
            Name="VideoControl"LoadedBehavior="Manual"UnloadedBehavior="Stop" >
      </MediaElement>
    <ButtonHeight="23"HorizontalAlignment="Left"Margin="15,0,0,13"
            Name="PlayButton"VerticalAlignment="Bottom"Width="75"
            Click="PlayClick">
      Play</Button>
    <ButtonHeight="23"HorizontalAlignment="Left"Margin="103,0,0,13"
            Name="PauseButton"VerticalAlignment="Bottom"Width="75"
            Click="PauseClick">
      Pause</Button>
    <ButtonHeight="23"Margin="191,0,186,13"Name="StopButton"
            VerticalAlignment="Bottom" Click="StopClick">
      Stop</Button>
  </Grid>

Listing 1.

The code behind looks like Listing 2. As you can see from this code, on the Windows1 constructor I set the Volume, Width, and Height of the control.

The Browse button click event handler calls OpenFileDialog, that lets us browse the files and sets the "MediaPathTextBox.Text" as the media file name.

The Play, Pause, and Stop button click handlers simply calls Play, Pause, and Stop methods of the MediaElement control.

public Window1()
{
    InitializeComponent();
    VideoControl.Volume = 100;
    VideoControl.Width = 440;
    VideoControl.Height = 280;
}

void BrowseClick(Object sender, EventArgs e)
{
    OpenFileDialog openDlg =new OpenFileDialog();
    openDlg.InitialDirectory = @"c:\";
    openDlg.ShowDialog();
    MediaPathTextBox.Text = openDlg.FileName;
}

void PlayClick(object sender, EventArgs e)
{
    if (MediaPathTextBox.Text.Length <= 0)
    {
        System.Windows.Forms.MessageBox.Show("Enter a valid media file");
        return;
    }
    VideoControl.Source = newUri(MediaPathTextBox.Text);
    VideoControl.Play();
 }
void PauseClick(object sender, EventArgs e)
{
    VideoControl.Pause();
}

void StopClick(object sender, EventArgs e)
{
    VideoControl.Stop();
}

Listing 2.

Download the attached source code for more details.