在 Java 中将日期格式 dd-MM-yyyy 更改为 yyyy-MM-dd
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Change date format dd-MM-yyyy to yyyy-MM-dd in Java
提问by Rana Depto
I was trying to convert date string 08-12-2017 to 2017-12-08(LocalDate). Here is what I tried-
我试图将日期字符串 08-12-2017 转换为 2017-12-08(LocalDate)。这是我尝试过的-
String startDateString = "08-12-2017";
LocalDate date = LocalDate.parse(startDateString);
System.out.println(date);
Also tried using formatter, but getting same result, an DateTimeParseException. How can I get an output like 2017-12-08, without getting an exception?
还尝试使用格式化程序，但得到相同的结果，DateTimeParseException。如何获得类似 2017-12-08 的输出，而不会出现异常？
回答by Joe Rakhimov
Try this (see update below)
试试这个（见下面的更新）
try {
String startDateString = "08-12-2017";
SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy");
SimpleDateFormat sdf2 = new SimpleDateFormat("yyyy-MM-dd");
System.out.println(sdf2.format(sdf.parse(startDateString)));
} catch (ParseException e) {
e.printStackTrace();
}
Update - Java 8
更新 - Java 8
String startDateString = "08-12-2017";
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd-MM-yyyy");
DateTimeFormatter formatter2 = DateTimeFormatter.ofPattern("yyyy-MM-dd");
System.out.println(LocalDate.parse(startDateString, formatter).format(formatter2));
回答by Hafsa Elif ?z?iftci
First you have to parse the string representation of your date-time into a Date object.
首先，您必须将日期时间的字符串表示形式解析为 Date 对象。
DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date date = (Date)formatter.parse("2011-11-29 12:34:25");
Then you format the Date object back into a String in your preferred format.
然后，您将 Date 对象格式化回您首选格式的 String。
DateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy");
String mydate = dateFormat.format(date);
