C# 语音识别，请教这篇文章哪位高手能帮忙解释上，看不懂。

C# 语音识别，请问这篇文章谁能帮忙解释下，看不懂。。。

C# code

using System.Speech.Recognition;namespace Douban{public partial class MainWindow : Window{SpeechRecognizer speechRecognizer;public MainWindow(){InitializeComponent();// if (Properties.Settings.Default.EnableSpeech)speechRecognizer = new SpeechRecognizer();}private void window_Loaded(object sender, RoutedEventArgs e){// if(Properties.Settings.Default.EnableSpeech)VoiceCommand();}private void VoiceCommand(){RegisterVoiceCommand(VoiceCommand_Close, "退出");RegisterVoiceCommand(VoiceCommand_Next, "下一首");RegisterVoiceCommand(VoiceCommand_Minimize, "最小化");RegisterVoiceCommand(VoiceCommand_Restore, "恢复");RegisterVoiceCommand(VoiceCommand_Pause, "暂停");RegisterVoiceCommand(VoiceCommand_Resume, "播放");}private void VoiceCommand_Resume(object sender, EventArgs e){if (mediaPlayer.MediaState != MediaState.Play){if (mediaPlayer.MediaUri != null){mediaPlayer.Play();pnlPlayer.SetPlayerStatus(true);}}}private void VoiceCommand_Pause(object sender, EventArgs e){if (mediaPlayer.MediaState == MediaState.Play){mediaPlayer.Pause();pnlPlayer.SetPlayerStatus(false);}}private void VoiceCommand_Close(object sender, EventArgs e){this.Close();}private void VoiceCommand_Next(object sender, EventArgs e){}private void VoiceCommand_Minimize(object sender, EventArgs e){this.WindowState = WindowState.Minimized;}private void VoiceCommand_Restore(object sender, EventArgs e){this.WindowState = WindowState.Normal;}private void RegisterVoiceCommand(EventHandler Callback, params string[] Args){Choices choices = new Choices();foreach (string arg in Args){choices.Add(arg);}Grammar grammar = new Grammar(new GrammarBuilder(choices));grammar.SpeechRecognized += delegate(object sender, SpeechRecognizedEventArgs e){EventHandler eventHandler = new EventHandler(Callback);Dispatcher.BeginInvoke(eventHandler, sender, e);};speechRecognizer.LoadGrammarAsync(grammar);}