java - 如何将日期时间从一个时区转换为另一个时区

Question

记录是根据美国时区保存的，但是如果我想向用户显示相同的记录，它应该将服务器日期时间(美国时区)转换为用户的日期时间和用户时区

Answer 1

如果您在 google 中输入“Java date change timezone”或“Javascript date change timezone”。您将得到以下结果之一:

在 Java 中(来源:http://www.coderanch.com/t/417443/java/java/Convert-Date-one-timezone-another)

Date date = new Date();  

DateFormat formatter = new SimpleDateFormat("dd MMM yyyy HH:mm:ss z");  
formatter.setTimeZone(TimeZone.getTimeZone("CET"));  

// Prints the date in the CET timezone  
System.out.println(formatter.format(date));  

// Set the formatter to use a different timezone  
formatter.setTimeZone(TimeZone.getTimeZone("IST"));  

// Prints the date in the IST timezone  
System.out.println(formatter.format(date));  

Javascript(来源:http://www.techrepublic.com/article/convert-the-local-time-to-another-time-zone-with-this-javascript/6016329)

// function to calculate local time
// in a different city
// given the city's UTC offset
function calcTime(city, offset) {

    // create Date object for current location
    d = new Date();

    // convert to msec
    // add local time zone offset
    // get UTC time in msec
    utc = d.getTime() + (d.getTimezoneOffset() * 60000);

    // create new Date object for different city
    // using supplied offset
    nd = new Date(utc + (3600000*offset));

    // return time as a string
    return "The local time in " + city + " is " + nd.toLocaleString();

}

// get Bombay time
alert(calcTime('Bombay', '+5.5'));