在实际测试中发现上一片文章（A class to play sound on netcf in CSharp）中介绍的播放声音的类在pda中运行正常，但却无法在pc中工作，简单分析了一下原因，发现是dll的问题，pc和pda播放声音时用的dll不同。pc中是winmm，而pda中则是coredll，项目需要在pc和pda上都可以运行，因此加入了动态判断功能，识别程序运行在pc还是pda中，从而加载不同的dll来播放声音，下面对是该类的一个封装：
using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;
namespace MiniCafe.Util
{
internal class NetHelpers
{
[Flags]
public enum PlaySoundFlags : int
{
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("winmm")]
public static extern bool PlaySound(string szSound, IntPtr hMod, PlaySoundFlags flags);
}
internal class NetCFHelpers
{
[Flags]
public enum PlaySoundFlags : int
{
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")]
public static extern bool PlaySound(string szSound, IntPtr hMod,PlaySoundFlags flags);
}
public class Sound
{
public static void Play(string strFileName)
{
if (Framework.IsNetCF)
{
//for pda
NetCFHelpers.PlaySound(strFileName, IntPtr.Zero,
NetCFHelpers.PlaySoundFlags.SND_FILENAME | NetCFHelpers.PlaySoundFlags.SND_ASYNC);
}
else
{
//for pc
NetHelpers.PlaySound(strFileName, IntPtr.Zero,
NetHelpers.PlaySoundFlags.SND_FILENAME | NetHelpers.PlaySoundFlags.SND_ASYNC);
}
}
}
}