客户端可选择服务端共享的mp3音乐，并下载后就可以直接播放音乐而不用再开额外的音乐播放器。改自以前师兄的暑假实习的。-Client Services client may choose to share mp3 music, and then can directly download music without having to play another extra music player. Changed since the summer vacation before my senio