如何获取今天的日期和当月最后一个日期之间的天数？

Question

所以我正在制作一个 Android 应用程序，我需要计算当前日期和当月最后一个日期之间的天数。

假设今天是 1/11/2017，当月的最后一个日期是 30/11/2017。所以天数是 30。因为 30 天后下个月就要开始了。

Answer 1

    Calendar calendar = Calendar.getInstance();
    int lastDay = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
    int currentDay = calendar.get(Calendar.DAY_OF_MONTH);
    int daysLeft = lastDay - currentDay;


    System.out.println("Last Day: " + lastDay);
    System.out.println("Current Day : " + currentDay);
    System.out.println("There are " + daysLeft + " days left in the month.");

输出

Last Day: 30
Current Day : 1
There are 29 days left in the month.