Application Security Testing: An Integral Part of DevOps
One of the first questions I get asked by my students is how to play movies or music through Visual Basic. I know of four different ways, depending on which Operating System you are on. Today I will cover the first option: Windows Media Player. Today we will learn how to embed Windows Media Player into our program and play any form of media through it.
Start a new Visual Basic Windows Application and add the following controls to it:
- Menu with the following Subitems
- Volume Up
- Volume Down
- Windows Media Player Control. Follow these steps:
- Right click your Toolbox
- Select Choose Items…
- Select the COM Tab
- Scroll Down to Windows Media Player
- If you don't find it on the list, Browse to the Wmp.dll file inside C:\Windows\System32
Your completed design should look more or less like Figure 1.
Figure 1 - Our Design
Add the KeyDown event to your Form, and enter the following:
Private Sub frmMedia_KeyDown(sender As Object, e As KeyEventArgs) Handles Me.KeyDown 'Determine Key Pressed - Form KeyPreview Is Set To True Select e.KeyCode Case Keys.Add ' Plus Key wmpPlayer.settings.volume = wmpPlayer.settings.volume + 2 ' Increase Volume Case Keys.Subtract 'Minus Key If wmpPlayer.settings.volume > 0 Then 'If Greater Than 0 wmpPlayer.settings.volume = wmpPlayer.settings.volume - 2 'Decrease Volume wmpPlayer.settings.mute = False 'Enable Mute Button Else '0 Or Less wmpPlayer.settings.mute = True 'Muted Is True, Disable Mute Button End If Case Keys.Divide '/ wmpPlayer.settings.mute = Not wmpPlayer.settings.mute 'Mute End Select End Sub
As mentioned earlier, because the KeyPreview Property is set to true for the Form, the Form intercepts all keyboard input. This is the most apt place to handle any of our 'hotkeys' for our program.
When Plus ( + ) is pressed, it increases the volume in increments of 2.
When Minus ( - ) is pressed, it makes sure that the volume is greater than 0, before enabling the Mute button.
When Divide ( / ) is pressed, it mutes the volume.
Now let us proceed with the File Menu's submenus.
Add the following three events:
Private Sub BrowseToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles BrowseToolStripMenuItem.Click 'Set Filter For OFD ofdOpen.Filter = "AVI Files|*.avi|MPG Files|*.mpg|MP4 Files|*.mp4|WMV Files|*.wmv|All Files|*.*" If ofdOpen.ShowDialog = Windows.Forms.DialogResult.OK Then 'If Valid File Selected wmpPlayer.URL = ofdOpen.FileName 'Play PlayPauseToolStripMenuItem.Text = "Pause" 'Change 'Play' To 'Pause' On Menu End If End Sub Private Sub ExitToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ExitToolStripMenuItem.Click Application.Exit() 'Exit End Sub Private Sub ResizeToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ResizeToolStripMenuItem.Click wmpPlayer.Size() = Me.ClientRectangle.Size 'Make Same Size As Form End Sub
The Browse menu item allows us to select AVI, MPG, MP4 as well as WMV options. Obviously we can add MP3 here as well, specifically for audio. Just a note: MP 4 files may not work if Windows Media Player doesn't have the correct codec to play them.
Exit, exits our application.
Resize, resizes the Media Player according to the form's size in the event of the form being resized.
Now, let us add the Player menu's sub items:
Private Sub VolumeUpToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles VolumeUpToolStripMenuItem.Click wmpPlayer.settings.volume = wmpPlayer.settings.volume + 2 'Increase Volume End Sub Private Sub VolumeDownToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles VolumeDownToolStripMenuItem.Click 'Same As When - Pressed If wmpPlayer.settings.volume > 0 Then wmpPlayer.settings.volume = wmpPlayer.settings.volume - 2 wmpPlayer.settings.mute = False Else wmpPlayer.settings.mute = True End If End Sub Private Sub MuteToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles MuteToolStripMenuItem.Click wmpPlayer.settings.mute = Not wmpPlayer.settings.mute 'Swith Between Mute & UnMuted End Sub Private Sub PlayPauseToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles PlayPauseToolStripMenuItem.Click If PlayPauseToolStripMenuItem.Text = "Play" Then 'Switch Between Playing & Pausing wmpPlayer.Ctlcontrols.play() PlayPauseToolStripMenuItem.Text = "Pause" Else wmpPlayer.Ctlcontrols.pause() PlayPauseToolStripMenuItem.Text = "Play" End If End Sub Private Sub StopToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles StopToolStripMenuItem.Click wmpPlayer.Ctlcontrols.stop() 'Stop End Sub Private Sub InvisibleToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles InvisibleToolStripMenuItem.Click ''Windows Media Player is embedded without any visible user interface wmpPlayer.uiMode = "invisible" End Sub Private Sub NoneToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles NoneToolStripMenuItem.Click 'Windows Media Player is embedded without controls, 'and with only the video or visualization window displayed wmpPlayer.uiMode = "none" End Sub Private Sub MiniToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles MiniToolStripMenuItem.Click 'Windows Media Player is embedded with the status window, 'play/pause, stop, mute, and volume controls shown in 'addition to the video or visualization window wmpPlayer.uiMode = "mini" End Sub
The first few items concerning the Volume, are identical to our KeyDown event. Yes, I could have made one central sub procedure for all, but this is afterall a basic introduction.
The Play menu item will switch between 'Play' and 'Pause' depending on the state of the player. If it is playing an item, it shows 'Pause'. If it was paused, it should show 'Play'.
Stop stops all media.
The Mode setting determines how the Windows Media Player object looks. This means that depending on what setting has been chosen, the buttons, volume controls, etc. might be displayed or not. You can feel free to experiment with that setting. For more information regarding the uimode property, have a look here.
There you have it, not too complicated hey? Nope. I am including the source files with this article. Check out Part 2 - Playing Youtube and Flash videos from Visual Basic.NET. That is very exciting, but don't let me get ahead of myself here. Until then, Cheers!
About the Author:
Hannes du Preez is a Microsoft MVP for Visual Basic for the fifth year in a row. He is a trainer at a South African-based company providing IT training in the Vaal Triangle. You could reach him at hannes [at] ncc-cla [dot] com