Question

我使用关闭按钮创建了这个简单的示例表单。

当不使用Interop.WMPLib.dll

时，一切都按预期工作

我已经看到其他应用程序使用它没有问题，但为什么在我添加行时不关闭Form进程：

SoundPlayer myPlayer = new SoundPlayer();

当然处理它：

if (myPlayer != null)
            {
                myPlayer.Dispose();
                myPlayer = null;
            }

表单关闭但调试器VS2008仍处于活动状态。表单项目和DLL仍处于活动状态。

如果您发送电子邮件至xdasleepsense@gmail.com，我可以将压缩项目发送给您。

以下是dll的类：

使用System; 使用System.Collections.Generic; 使用System.Text; 使用System.Threading; 使用System.Runtime.InteropServices; 使用WMPLib;

命名空间WindowsMobile.Utilities { public delegate void SoundPlayerStateChanged（SoundPlayer sender，SoundPlayerState newState）;

public enum SoundPlayerState
{
    Stopped,
    Playing,
    Paused,
}


public class SoundPlayer : IDisposable
{
    [DllImport("coredll")]
    public extern static int waveOutSetVolume(int hwo, uint dwVolume);

    [DllImport("coredll")]
    public extern static int waveOutGetVolume(int hwo, out uint dwVolume);

    WindowsMediaPlayer myPlayer = new WindowsMediaPlayer();

    public SoundPlayer()
    {
        myPlayer.uiMode = "invisible";
        myPlayer.settings.volume = 100;
    }

    string mySoundLocation = string.Empty;

    public string SoundLocation
    {
        get { return mySoundLocation; }
        set { mySoundLocation = value; }
    }

    public void Pause()
    {
        myPlayer.controls.pause();
    }

    public void PlayLooping()
    {
        Stop();
        myPlayer.URL = mySoundLocation;
        myPlayer.settings.setMode("loop", true);
    }

    public int Volume
    {
        get { return myPlayer.settings.volume; }
        set { myPlayer.settings.volume = value; }
    }

    public void Play()
    {
        Stop();
        myPlayer.URL = mySoundLocation;
        myPlayer.controls.play();
    }

    public void Stop()
    {
        myPlayer.controls.stop();
        myPlayer.close();
    }

    #region IDisposable Members

    public void Dispose()
    {
        try
        {
            Stop();
        }
        catch (Exception)
        {
        }
        // need this otherwise the process won't exit?!
        try
        {
            int ret = Marshal.FinalReleaseComObject(myPlayer);
        }
        catch (Exception)
        {
        }
        myPlayer = null;
        GC.Collect();
    }

    #endregion
}
}

Answer 1

MessageBox或Below解决了它。 THX。

public void Dispose()
    {
        try
        {
            Stop();
        }
        catch (Exception)
        {
        }
        // need this otherwise the process won't exit?!
        try
        {
            int ret = Marshal.FinalReleaseComObject(myPlayer);
        }
        catch (Exception)
        {
        }
        myPlayer = null;
        GC.Collect();

        //If you don't do this, it will not quit
        //http://www.eggheadcafe.com/software/aspnet/31363254/media-player-freezing-app.aspx
        for (int s = 0; s < 100; s++)
        {
            Application.DoEvents();
            Thread.Sleep(1);
        }
        GC.WaitForPendingFinalizers();

        //MessageBox.Show("Application Exiting");
    }

Answer 2

我刚从此链接中找到：http://software.itags.org/pocketpc-developer/163455/ 一个提示...

所以我添加了一个消息框：

public void Dispose() 
    { 
        try 
        { 
            Stop(); 
        } 
        catch (Exception) 
        { 
        } 
        // need this otherwise the process won't exit?! 
        try 
        { 
            int ret = Marshal.FinalReleaseComObject(myPlayer); 
        } 
        catch (Exception) 
        { 
        } 
        myPlayer = null; 
        GC.Collect(); 

        **MessageBox.Show("Application Exiting");**

    }

一旦我点击OK，调试器也认为它已经完成了。当然我不能让用户点击OK。

那么这里发生了什么？

为什么在使用播放器时不会关闭这个简单的移动表格

2 个答案: