这里使用了一个单例的SocketManager类：
new Socket();
2:
3: conn.addEventListener(Event.CLOSE, onSocketCloseHandler);
4: conn.addEventListener(Event.CONNECT, onSocketConnectHandler);
5: conn.addEventListener(IOErrorEvent.IO_ERROR, onSocketIOErrorHandler);
6: conn.addEventListener(SecurityErrorEvent.SECURITY_ERROR, onSocketSecurityHandler);
7: conn.addEventListener(ProgressEvent.SOCKET_DATA, onSocketDataHandler);