WinCE系统播放wav声音文件的实现方法

标 题: WinCE系统播放wav声音文件的实现方法

发信站: 放鹤亭 BBS (Tue Apr 15 12:55:40 2008), 本站(bbs.cumt.edu.cn)

此示例在WinCE5.0 + .Net CF2.0环境下运行成功

此示例需要引用下面的命名空间：

System

System.IO

System.Reflection

System.Runtime.InteropServices

System.Windows.Forms

此示例演示如何使用平台调用来播放两个WAV文件：一个为嵌入的资源，另一个为内容。

此示例定义了一个Sound类，该类通过WinCE的CoreDll.dll提供下面的本机代码功能：

1、使用文件名或流播放声音的平台调用方法声明。

2、用于在平台调用方法调用中传递参数的位值枚举。

3、Play方法，用于调用正确的平台调用方法来播放单独的文件或嵌入的资源。

第一步：将 Sound 类添加到项目中。

public class Sound

{

private byte[] m_soundBytes;

private string m_fileName;

private enum Flags {

SND_SYNC = 0x0000, /* play synchronously (default) */

SND_ASYNC = 0x0001, /* play asynchronously */

SND_NODEFAULT = 0x0002, /* silence (!default) if sound not found */

SND_MEMORY = 0x0004, /* pszSound points to a memory file */

SND_LOOP = 0x0008, /* loop the sound until next sndPlaySound */

SND_NOSTOP = 0x0010, /* don't stop any currently playing sound */

SND_NOWAIT = 0x00002000, /* don't wait if the driver is busy */

SND_ALIAS = 0x00010000, /* name is a registry alias */

SND_ALIAS_ID = 0x00110000, /* alias is a predefined ID */

SND_FILENAME = 0x00020000, /* name is file name */

SND_RESOURCE = 0x00040004 /* name is resource name or atom */

}

[DllImport("CoreDll.DLL", EntryPoint="PlaySound", SetLastError=true)]

private extern static int WCE_PlaySound(string szSound, IntPtr hMod, int flags);

[DllImport("CoreDll.DLL", EntryPoint="PlaySound", SetLastError=true)]

private extern static int WCE_PlaySoundBytes (byte[] szSound, IntPtr hMod, int flags);

/// <summary>

/// Construct the Sound object to play sound data from the specified file.

/// </summary>

public Sound (string fileName) {

m_fileName = fileName;

}

/// <summary>

/// Construct the Sound object to play sound data from the specified stream.

/// </summary>

public Sound(Stream stream) {

// read the data from the stream

m_soundBytes = new byte [stream.Length];

stream.Read(m_soundBytes, 0,(int)stream.Length);

}

/// <summary>

/// Play the sound

/// </summary>

public void Play () {

// if a file name has been registered, call WCE_PlaySound,

// otherwise call WCE_PlaySoundBytes

if (m_fileName != null)

WCE_PlaySound(m_fileName, IntPtr.Zero, (int) (Flags.SND_ASYNC | Flags.SND_FILENAME));

else

WCE_PlaySoundBytes (m_soundBytes, IntPtr.Zero, (int) (Flags.SND_ASYNC | Flags.SND_MEMORY));

}

}

第二步：添加用于创建 Sound 类的实例和播放文件的方法，例如，在某按钮的 Click 事件中。

private void btnEmbedded_Click(object sender, System.EventArgs e) {

Sound sound = new Sound (Assembly.GetExecutingAssembly().GetManifestResourceStream("SoundSample.chimes.wav"));

sound.Play();

}

private void btnFile_Click(object sender, System.EventArgs e) {

Sound sound = new Sound (@"Program Files/SoundSample/dingdang.wav");

sound.Play();

}

编译代码

OK