VC++获取某个时间段跨度，得出多少天的程序源码，举例来说，本例中的程序是获取2012年1月1日距现在还有多少天，经过自己的思考总算写出了程序，了解了原理后，你就能方便的使用到其它的VC项目中，欢迎您批评指正。

-VC++ for a time span, the number of days the program source derived, for example, in this case the procedure is to obtain 1 January 2012 how many days from now, after finally write in your own thinking process understand the principles, you can easily use to other VC projects, you are welcome criticism correction.