vlc的應用之三：動態調用vlc-0.9.4的libvlc.dll

請移步https://higoge.github.io/，全部下載資料在那個博客都能找到。謝謝。 

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    vlc-0.9.4提供的libvlc.dll是能夠動態調用的，Jeremiah這一篇博客就介紹下如何用C#和WinForm框架調用libvlc.dll做個簡易播放器。

 

    1. vs2005新建工程，將vlc-0.9.4的libvlc.dll，libvlccore.dll，plugins目錄所有拷貝到工程目錄下面\bin\Debug中。

 

    2. 建立異常結構體

using System;
using System.Collections.Generic;
using System.Text;

namespace MyOwnPlayer
{
        //異常結構體
        public struct ExceptionStruct
        {
                private int raised;
                private int code;
                private string message;
        }

        class MediaException
        {
        }
}

 

    3. CoreHandle和Core類

using System;
using System.Runtime.InteropServices;

namespace MyOwnPlayer
{
        class CoreHandle : SafeHandle
        {
                //構造方法
                public CoreHandle()
                        : base(IntPtr.Zero, true)
                {
                }

                //重寫的方法
                public override bool IsInvalid
                {
                        get { return handle == IntPtr.Zero; }
                }

                protected override bool ReleaseHandle()
                {
                        if (!IsInvalid)
                        {
                                libvlc_release(this);
                                handle = IntPtr.Zero;
                        }
                        return true;
                }

                protected override void Dispose(bool disposing)
                {
                        ReleaseHandle();
                        base.Dispose(disposing);
                }

                //Dll動態導入
                [DllImport("libvlc")]
                private static extern void libvlc_release(CoreHandle coreHandle);
        }
}

 

using System;
using System.Runtime.InteropServices;

namespace MyOwnPlayer
{
        class Core
        {
                //coreHandle字段和屬性
                private CoreHandle coreHandle;
                public CoreHandle CoreHandle
                {
                        get { return coreHandle; }
                }
                
                //構造方法
                public Core(string[] argv, ref ExceptionStruct ex)
                {
                        coreHandle = libvlc_new(argv.Length, argv, ref ex);
                }

                //Dll動態導入
                [DllImport("libvlc")]
                private static extern CoreHandle libvlc_new(int argc, string[] args, ref ExceptionStruct ex);
        }
}

 

    3. MediaHandle和Media類，注意裏面的非英文路徑處理方法。

using System;
using System.Runtime.InteropServices;

namespace MyOwnPlayer
{
        class MediaHandle : SafeHandle
        {
                //構造方法
                public MediaHandle()
                        : base(IntPtr.Zero, true)
                {
                }

                //重寫的方法
                public override bool IsInvalid
                {
                        get { return handle == IntPtr.Zero; }
                }

                protected override bool ReleaseHandle()
                {
                        if (!IsInvalid)
                        {
                                libvlc_media_release(this);
                                handle = IntPtr.Zero;
                        }
                        return true;
                }

                protected override void Dispose(bool disposing)
                {
                        ReleaseHandle();
                        base.Dispose(disposing);
                }

                //Dll動態導入
                [DllImport("libvlc")]
                private static extern void libvlc_media_release(MediaHandle mediaHandle);                
        }
}

 

using System;
using System.Text;
using System.Runtime.InteropServices;

namespace MyOwnPlayer
{
        class Media
        {
                //mediaHandle字段和屬性
                private MediaHandle mediaHandle;
                public MediaHandle MediaHandle
                {
                        get { return mediaHandle; }
                }

                //構造方法                
                public Media(CoreHandle coreHandle, String filename, ref ExceptionStruct ex)
                {
                        //c#爲UTF-16編碼, libvlc.dll爲UTF-8編碼, 須要轉換.
                        UTF8Encoding utf8 = new UTF8Encoding();
                        mediaHandle = libvlc_media_new(coreHandle, utf8.GetBytes(filename), ref ex);
                }
                
                //Dll動態導入
                [DllImport("libvlc")]
                private static extern MediaHandle libvlc_media_new
                        (CoreHandle coreHandle, [MarshalAs(UnmanagedType.LPArray)] byte[] link, ref ExceptionStruct ex);
                }
}

 

    5. MediaPlayerHandle和MediaPlayer類

using System;
using System.Runtime.InteropServices;

namespace MyOwnPlayer
{
        class MediaPlayerHandle : SafeHandle
        {
                //構造方法
                public MediaPlayerHandle()
                        : base(IntPtr.Zero, true)
                {
                }

                //重寫的方法
                public override bool IsInvalid
                {
                        get { return handle == IntPtr.Zero; }
                }

                protected override bool ReleaseHandle()
                {
                        if (!IsInvalid)
                        {
                                libvlc_media_player_release(this);                                handle = IntPtr.Zero;
                        }
                        return true;
                }

                protected override void Dispose(bool disposing)
                {
                        ReleaseHandle();
                        base.Dispose(disposing);
                }

                //Dll動態導入
                [DllImport("libvlc")]
                private static extern void libvlc_media_player_release(MediaPlayerHandle mediaPlayerHandle);
        }
}

 

using System;
using System.Runtime.InteropServices;

namespace MyOwnPlayer
{
        class MediaPlayer
        {
                //mediaPlayerHandle字段和屬性
                private MediaPlayerHandle mediaPlayerHandle;
                public MediaPlayerHandle MediaPlayerHandle
                {
                        get { return mediaPlayerHandle; }
                }

                //構造方法
                public MediaPlayer(MediaHandle mediaHandle, ref ExceptionStruct ex)
                {
                        mediaPlayerHandle = libvlc_media_player_new_from_media(mediaHandle, ref ex);
                }

                //設置父窗口
                public void VedioSetParent(CoreHandle coreHandle, IntPtr hDT, ref ExceptionStruct ex)
                {
                        libvlc_video_set_parent(coreHandle, hDT, ref ex);
                }

                //播放
                public void Play(ref ExceptionStruct ex)
                {
                        libvlc_media_player_play(mediaPlayerHandle, ref ex);
                }

                //中止
                public void Stop(ref ExceptionStruct ex)
                {
                        libvlc_media_player_stop(mediaPlayerHandle, ref ex);
                }

                //Dll動態導入
                [DllImport("libvlc")]
                private static extern MediaPlayerHandle libvlc_media_player_new_from_media(MediaHandle libvlc_media_handle, ref ExceptionStruct ex);

                [DllImport("libvlc")]
                private static extern void libvlc_video_set_parent(CoreHandle coreHandle, IntPtr hDT, ref ExceptionStruct ex);

                [DllImport("libvlc")]
                private static extern void libvlc_media_player_play(MediaPlayerHandle mediaPlayerHandle, ref ExceptionStruct ex);

                [DllImport("libvlc")]
                private static extern void libvlc_media_player_stop(MediaPlayerHandle mediaPlayerHandle, ref ExceptionStruct ex);
        }
}

 

    6. 基本工做作好了。下一步創建一個Form，裏面畫一個Panel(播放容器)，畫一個Textbox(播放地址)，畫一個Button(播放按鈕)，Button的點擊事件爲：

private void button1_Click(object sender, EventArgs e)
{
        //要播放的文件的uri
        string uri = this.textBox1.Text;

         //進行播放的控件的句柄
        IntPtr hdl = this.panel1.Handle;

         //播放參數
        string[] argv = new string[] { "-I", "--ignore-config" };

         //vlc對象的建立
        ExceptionStruct ex = new ExceptionStruct();
        Core core = new Core(argv, ref ex);
        Media media = new Media(core.CoreHandle, uri, ref ex);
        MediaPlayer player = new MediaPlayer(media.MediaHandle, ref ex);

         //垃圾回收
        GC.Collect();

         //播放
        player.VedioSetParent(core.CoreHandle, hdl, ref ex);
        player.Play(ref ex);

         //繼續回收垃圾等相關操做
        GC.Collect();
        GC.WaitForPendingFinalizers();
}

 

    7. 基本的播放功能就是這樣實現的。其餘接口請參考源碼下面的\include\vlc\libvlc.h文件，裏面有比較詳細的對外接口的說明。

 

    8. 以上代碼已經發送到附件中(MyOwnPlayer.rar)，參考網址的樓主寫的代碼也在附件中(Marx_libvlc_wrapper(2).zip)。調試附件請注意第1步。

   

參考網址：

1. [url]http://forum.videolan.org/viewtopic.php?f=14&t=47385&st=0&sk=t&sd=a&hilit=C%23+wrapper[/url]