我怎样才能玩上使用MonoTouch的iPhone的声音？

Question

我要寻找类似

PlaySound (uint frequency)

是否存在？

Answer 1

从方法文档在： http://wiki.monotouch.net/HowTo/Sound/Play_a_Sound_or_Alert

var sound = SystemSound.FromFile (new NSUrl ("File.caf"));  
sound.PlaySystemSound (); 

Answer 2

我不知道单声道，但在iPhone SDK不容易那么容易创建和播放声音。其它替代方案是提供声音作为一个文件和播放，或创建代表一个正弦波的阵列，并且在音频包装包裹它，并将它传递给许多声音API中的一个。

如果单证明是一样的限制，然后搜索stackoverflow.com为系统声音服务和AVAudioPlayer为起点。

下面两种方法来播放声音文件：

SoundEffect.c（基于苹果）

#import "SoundEffect.h"

@implementation SoundEffect
+ (id)soundEffectWithContentsOfFile:(NSString *)aPath {
    if (aPath) {
        return [[[SoundEffect alloc] initWithContentsOfFile:aPath] autorelease];
    }
    return nil;
}

- (id)initWithContentsOfFile:(NSString *)path {
    self = [super init];

    if (self != nil) {
        NSURL *aFileURL = [NSURL fileURLWithPath:path isDirectory:NO];

        if (aFileURL != nil)  {
            SystemSoundID aSoundID;
            OSStatus error = AudioServicesCreateSystemSoundID((CFURLRef)aFileURL, &aSoundID);

            if (error == kAudioServicesNoError) { // success
                _soundID = aSoundID;
            } else {
                NSLog(@"Error %d loading sound at path: %@", error, path);
                [self release], self = nil;
            }
        } else {
            NSLog(@"NSURL is nil for path: %@", path);
            [self release], self = nil;
        }
    }
    return self;
}

-(void)dealloc {
    AudioServicesDisposeSystemSoundID(_soundID);
    NSLog(@"Releasing in SoundEffect");

    [super dealloc];
//  self = nil;
}

-(void)play {
    AudioServicesPlaySystemSound(_soundID);
}

-(void)playvibe {
    AudioServicesPlayAlertSound(_soundID);
}
+(void)justvibe {
    AudioServicesPlayAlertSound(kSystemSoundID_Vibrate);
}

@end

SoundEffect.h：

#import <AudioToolbox/AudioServices.h>

@interface SoundEffect : NSObject {
    SystemSoundID _soundID;
}

+ (id)soundEffectWithContentsOfFile:(NSString *)aPath;
- (id)initWithContentsOfFile:(NSString *)path;
- (void)play;
- (void)playvibe;
+ (void)justvibe;
@end

如何使用它：

// load the sound
    gameOverSound = [[SoundEffect alloc] initWithContentsOfFile:[mainBundle pathForResource:@"buzz" ofType:@"caf"]];
// play the sound
    [gameOverSound playvibe];

这是当你想在同一个卷iPhone的音量控制设置播放声音是有用的，你就不会需要停止或暂停的声音。

另一种方法是：

+ (AVAudioPlayer *) newSoundWithName: (NSString *) name;
{

    NSString *soundFilePath = [[NSBundle mainBundle] pathForResource: name ofType: @"caf"];

    NSURL *fileURL = [[NSURL alloc] initFileURLWithPath: soundFilePath];

    AVAudioPlayer *newPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL: fileURL
                                                                      error: nil];
    [fileURL release];
// if the sound is large and you need to preload it:
    [newPlayer prepareToPlay];
    return (newPlayer);
}

和使用它（你可以看到所有的演员，当你与AVAudioPlayer去）：

timePassingSound = [AVAudioPlayer newSoundWithName:@"ClockTicking"];
[timePassingSound play];    
// change the volume
[timePassingSound volume:0.5];
// pause to keep it at the same place in the sound
[timePassingSound pause];    
// stop to stop completely, and go to beginning
[timePassingSound stop];    
// check to see if sound is still playing
[timePassingSound isPlaying];