Question

返回＆＃34;关闭时间＆＃34;的确切字符串从我的json结果下面。它似乎是24小时的时间格式。我做了一点搜索，发现它不是HH：MM：SS所需的格式。什么是将其转换为12小时上午PM时间的有效方法。 Thanks.`

String closingTime = "2100";
//Desired output: String closingTime = "9:00 pm"

Answer 1

我建议将时间解析为Calendar对象。这使得用给定的时间实际做事很容易，而不是仅仅将其作为字符串处理

Calendar time = Calendar.getInstance();

//Calendar.HOUR_OF_DAY is in 24-hour format
time.set(Calendar.HOUR_OF_DAY, closingTime.substring(0,2));

time.set(Calendar.MINUTE, closingTime.substring(2,4));

//Calendar.HOUR is in 12-hour format
System.out.print(time.get(Calendar.HOUR) + ":" + time.get(Calendar.MINUTE) + " " + time.get(Calendar.AM_PM));

以上代码将打印出来＆＃34; 9:00 PM＆＃34;如果你给它＆＃34; 2100＆＃34;，但内部的数据存储为millis，所以如果你需要，你可以用它做更多的事情。

修改上面的代码不正确，更像是伪代码，正如提问者所说，他提出了以下更完整的代码：

String closingTime = "2101"; //getInstance() will return the current millis, so changes will be made relative to the current day and time Calendar time = Calendar.getInstance(); // Calendar.HOUR_OF_DAY is in 24-hour format time.set(Calendar.HOUR_OF_DAY, Integer.parseInt(closingTime.substring(0, 2))); // time.get(Calendar.MINUTE) returns the exact minute integer e.g for 10:04 will show 10:4 // For display purposes only We could just return the last two substring or format Calender.MINUTE as shown below time.set(Calendar.MINUTE, Integer.parseInt(closingTime.substring(2, 4))); String minute = String.format("%02d", time.get(Calendar.MINUTE)); // time.get(Calendar.AM_PM) returns integer 0 or 1 so let's set the right String value String AM_PM = time.get(Calendar.AM_PM) == 0 ? "AM" : "PM"; // Calendar.HOUR is in 12-hour format System.out.print("...\n" + time.get(Calendar.HOUR) + ":" + minute + " " + AM_PM);

Answer 2

public static Date getDateFromString(String format, String dateStr) {

        DateFormat formatter = new SimpleDateFormat(format);
        Date date = null;
        try {
            date = (Date) formatter.parse(dateStr);
        } catch (ParseException e) {
            e.printStackTrace();
        }

        return date;
    }

/////////////////////

public static String getCurrentDate(String format) {
        SimpleDateFormat sdfFrom = new SimpleDateFormat(format);
        Calendar currentTime = Calendar.getInstance();
        return (sdfFrom.format(currentTime.getTime()));
    }

将字符串在24小时时间内转换为12小时上午时间

2 个答案: