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Playing with Windows Media Player

Microsoft has given ability to its development tool to suit the requirement as per developer wish. I had a requirement which needs to play multiple instances of media player on a single monitor. As a feature we know Media player can have only one instance running at a time. So I was scratching my head and finally a solution struck me, which is embedding multiple Media player instances on a single Win Form.

I've used C#.net and Windows Media Player library to solve the problem. Let's a have a look in the below sample program, the code is quite self explanatory. This sample code created an array of 2 Windows Media player instances and playing two audio (mp3) files simultaneously.

The Recreate button destroys the previous instances and creates two more new one. This is a very basic code and it can be modified as per more complex requirement. However, running large number of multiple instances of Windows Media Player isn't advisable.

using System;
using System.Collections.Generic;
using System.Windows.Forms;
using AxWMPLib;
using WMPLib;
using System.Runtime.InteropServices;

namespace MediaPlayerDemo
{
    public partial class Form1 : Form
    {
        AxWindowsMediaPlayer[] player;
        private IWMPMedia theMedia;
        private IWMPPlaylist mediaPlaylist;
          
        public Form1()
        {
            InitializeComponent();
            CreateMediaPlayer(2);
        }

        private void CreateMediaPlayer(int numOfPlayer)
        {
            this.player = new AxWindowsMediaPlayer[numOfPlayer];

            for (int i = 0; i < numOfPlayer; i++)
            {
                player[i] = new AxWindowsMediaPlayer();
                ((System.ComponentModel.ISupportInitialize)(this.player[i])).BeginInit();
               
                // Player
                this.player[i].Enabled = true;
                this.player[i].Location = new System.Drawing.Point((24 + (i*200)), 8);
                this.player[i].Name = "Player";
                this.player[i].Size = new System.Drawing.Size(192, 152);
                this.player[i].TabIndex = 0;
                this.player[i].TabStop = false;
                this.player[i].PlayStateChange += new AxWMPLib.
_WMPOCXEvents_PlayStateChangeEventHandler(this.Player_PlayStateChange);

                this.Controls.Add(this.player[i]);

                ((System.ComponentModel.ISupportInitialize)(this.player[i])).EndInit();

                if (i == 0)
                {
                    mediaPlaylist = player[i].mediaCollection.getByAttribute("MediaType", "audio");
                }
                theMedia = mediaPlaylist.get_Item(i);
                player[i].currentMedia = theMedia;
            }
        }

        private void Player_PlayStateChange(object sender, AxWMPLib.
                        _WMPOCXEvents_PlayStateChangeEvent e)
        {
            WMPPlayState newState = (WMPPlayState)e.newState;
            switch (newState)
            {
                case WMPPlayState.wmppsBuffering:
                    break;

                case WMPPlayState.wmppsMediaEnded:
                    break;

                case WMPPlayState.wmppsPaused:
                    break;

                case WMPPlayState.wmppsPlaying:
                    break;

                case WMPPlayState.wmppsReady:
                    break;

                case WMPPlayState.wmppsReconnecting:
                    break;

                case WMPPlayState.wmppsScanForward:
                    break;

                case WMPPlayState.wmppsScanReverse:
                    break;

                case WMPPlayState.wmppsStopped:
                    break;

                case WMPPlayState.wmppsTransitioning:                
                    break;

                case WMPPlayState.wmppsWaiting:                
                    break;

                default:              
                    break;
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            for (int i = 0; i < player.Length; i++)
            {
                if (player[i] != null)
                {
                    player[i].Ctlcontrols.stop();
                    if (player[i].playState == WMPLib.WMPPlayState.wmppsStopped)
                    {
                        player[i].close();
                        this.player[i].PlayStateChange -= new AxWMPLib.
_WMPOCXEvents_PlayStateChangeEventHandler(this.Player_PlayStateChange);
                       
                        Marshal.FinalReleaseComObject(player[i].currentMedia);
                        Marshal.FinalReleaseComObject(player[i].mediaCollection);
                        Marshal.FinalReleaseComObject(player[i].playlistCollection);
                        Marshal.FinalReleaseComObject(player[i].Ctlcontrols);
                        Marshal.FinalReleaseComObject(player[i].currentPlaylist);
                        player[i].Dispose();
                        player[i] = null;
                        this.Controls.Remove(player[i]);
                    }
                }
            }
            Marshal.FinalReleaseComObject(mediaPlaylist);
            player = null;
            GC.Collect();
            CreateMediaPlayer(2);
        }
    }
}

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