写log文件的一个类，当然也可以用作记录适时数据使用。该类使用了临界区、事件、文件读写、线程等技术，是学习这些技术非常有参考价值的实例.-write the log file a class, of course, can also be used for recording time data access. The use of such a critical, events, document literacy, threading technology, learning technol