让你app中的的文字合成语音

    AVSpeechSynthesizer *synthesizer = [[AVSpeechSynthesizer alloc] init];
    //设置文字
    AVSpeechUtterance *utterance =
    [AVSpeechUtterance speechUtteranceWithString:@"嗨，我是onebyte!"];
    //设置语速
    utterance.rate = AVSpeechUtteranceMaximumSpeechRate / 4.0f;
    //设置语种
    utterance.voice = [AVSpeechSynthesisVoice voiceWithLanguage:@"zh-CN"];
    [synthesizer speakUtterance:utterance];