Date Calculator(日期计算器)是一个日期计算器。

Date Calculator calculates the number of days, weeks, months or work days between 2 dates. If the duration is given, one of the dates is calculated. The field that was changed first is calculated. For example, if you change the end date, then the start date and then change the duration, the end date is calculated. When the program first starts, the calculation order is; start date, end date then duration. Changing the units of the duration does not affect which field is calculated。