Question

我的应用程序非常简单，它由一个字符串变量组成，其中包含日期和时间，从该字符串我只需要获取时间并将其转换为毫秒，以便我可以将该毫秒传递给警报管理器触发警报。

以下是我的MainActivity的代码：

   try {
        String string = "Mon, 10 Mar 2017 03:26:00 p.m.";
        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.HOUR_OF_DAY, Integer.parseInt(string.substring(17, 19)));
        calendar.set(Calendar.MINUTE, Integer.parseInt(string.substring(20, 22)));
        calendar.set(Calendar.AM_PM, string.contains("a.m.") ? 0 : 1);
        Toast.makeText(getApplicationContext(), "cal: " + calendar.getTime()+ " , milli sec: "+calendar.getTimeInMillis(), Toast.LENGTH_LONG).show();
    } catch (Exception e) {
        Toast.makeText(getApplicationContext(), "exe: " + e, Toast.LENGTH_LONG).show();
    }

当我打印 calendar.getTime 时，我同时获得日期和时间，即; Tue Mar 14 15:26:45 GMT + 2017年5月30日，而不是我需要获得 15:26:45 值并将该值转换为毫秒。

Answer 1

尝试使用它：

try {
    String string = "Mon, 10 Mar 2017 03:26:00 p.m.";
    Calendar calendar = Calendar.getInstance();
    calendar.set(Calendar.HOUR, Integer.parseInt(string.substring(17, 19)));
    calendar.set(Calendar.MINUTE, Integer.parseInt(string.substring(20, 22)));
    calendar.set(Calendar.AM_PM, string.contains("a.m.") ? 0 : 1);
    DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
    Toast.makeText(getApplicationContext(), "cal: " + dateFormat.format(calendar.getTime())+ " , milli sec: "+calendar.getTimeInMillis(), Toast.LENGTH_LONG).show();
} catch (Exception e) {
    Toast.makeText(getApplicationContext(), "exe: " + e, Toast.LENGTH_LONG).show();
}

Answer 2

您可以轻松使用calendar.getTimeInMillis()来获取毫秒数。

Answer 3

试试这个

   SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
    sdf.setTimeZone(TimeZone.getTimeZone("UTC"));

    String inputString = "00:01:30.500";

    Date date = sdf.parse("1970-01-01 " + inputString);
    System.out.println("in milliseconds: " + date.getTime());

Answer 4

请尝试以下代码：

try {
    String string = "Mon, 10 Mar 2017 03:26:00 p.m.";
    Calendar calendar = Calendar.getInstance();
    calendar.set(Calendar.HOUR_OF_DAY, Integer.parseInt(string.substring(17, 19)));
    calendar.set(Calendar.MINUTE, Integer.parseInt(string.substring(20, 22)));
    calendar.set(Calendar.AM_PM, string.contains("a.m.") ? 0 : 1);
    calendar.getTimeInMillis();
    SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
    String time = sdf.format(new Date(calendar.getTimeInMillis()));
    long timeinmili=0;
    try {
        Date date1 = sdf.parse(time);
        timeinmili = date1.getTime();
    } catch (ParseException e) {
        e.printStackTrace();
    }
    System.out.println("Time in Mili Seconds :"+timeinmili );
} catch (Exception e) {
    e.printStackTrace();
}

如何从android中的字符串获取时间（以毫秒为单位）？

4 个答案: