实现对c盘根目录下Test.xls的文件中指定行数据的导出。做这个程序的目的是因为有一张excel表，有好几千行的数据，每一行都是以时间开头，每隔2秒钟一行数据

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实现对c盘根目录下Test.xls的文件中指定行数据的导出。做这个程序的目的是因为有一张excel表，有好几千行的数据，每一行都是以时间开头，每隔2秒钟一行数据，现在需要将其每隔15分钟取一个数据，由于源数据中有缺失的，就不能按没450行取一行，只能先将时间导成字符串型，进行判断，再输出-C realize the root directory of the file under the specified Test.xls line derived data. The purpose of this procedure to do because there is an excel sheet, has thousands of lines of data, each line are based on time at the beginning of every 2 seconds, and his data, and now needs to be taken every 15 minutes a data, as the source data There are missing, it can not be 450 by not taking his line, only first time derivative into a string type, judge, and then output