Windows Mobile 6.5 SndPlayAsync - C# wrapper?
I'm implementing mp3 playback on Windows Mobile 6.5. I need to use SndPlayAsync API function since I don't want to block calling thread until the file is played (SndPlaySync blocks until the audio file is playing). Unfortunately the SndPlayAsync method takes sound handle instead of sound file path as parameter so there's a need to open the handle before and release of it after playback. The problem is that I don't have any information about the playback completion in this API. Did anybody use a C# wrapper for this API? Where can I get one? I've looked up O开发者_运维知识库PENNETCF but they seem not to support this API.
Regards
You have to call SndOpen first to get the handle. Looking at the docs, the declarations would be something along these lines:
[DllImport("coredll", SetLastError=true)]
public static extern int SndOpen(string fileName, out IntPtr handle);
[DllImport("coredll", SetLastError=true)]
public static extern int SndPlayAsync (IntPtr handle, int flags);
[DllImport("coredll", SetLastError=true)]
public static extern int SndClose(IntPtr handle);
So you'd use something like this to call it:
IntPtr handle;
var result = SndOpen("myfile.mp3", out handle);
if(result == 0) SndPlayAsync(handle, 0);
...
SndClose(handle);
If you are using .NET CF there is no reason to create a wrapper, you can just use the System.Media.SoundPlayer class to handle it. There are several options including PlaySync which will play the sound synchronously.
For instance:
string path = "\\Program Files\\SNAP.App.CE\\Content\\5LongLow.wav";
System.Media.SoundPlayer player = new System.Media.SoundPlayer(path);
player.PlaySync();
You can also put it in a separate thread if you don't want to block the UI thread.
You can use SndGetWaitHandle to get a handle to an event which will be signaled when the sound is finished playing. You can use the WaitForSingleObject API to wait or test if the event has been set.
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