/**
* This snippet of JavaScript returns the current time
* in a particular time zone when loaded in a client's web browser.
* I created this so that people back home in the U.S. would know what time
* it was in India when reading my India blog.
*
* Michael Bolin
* http://www.bolinfest.com/india04/
*
* KNOWN ISSUES:
*
* (1) This code has not been tested to see if it correctly handles
* daylight saving time.
* (2) The timezone of the Date returned by getForeignDate() will not
* be correct: see doc comment for getForeignDate() for details.
*
* This code may be copied and used freely so long as
* the doc comments remain unchanged.
*/
/**
* Sample usage:
*
* (1) Set DESIRED_OFFSET to the appropriate GMT offset. For example,
* if you wanted to get the time in India (which is GMT +05:30),
* you should have:
*
* var DESIRED_OFFSET = 5.5;
*
* (2) Include the following inside the tag:
*
*
*
* (3) Put the following somewhere in the tag to display the time:
*
*
*
*/
/** The offset of the time (in hours) that getForeignDate() returns */
var DESIRED_OFFSET = 5.5; // e.g., use 5.5 for India (GMT +05:30)
/** the number of milliseconds per hour: a constant */
var MILLIS_PER_HOUR = 1000 * 60 * 60;
/**
* returns a JavaScript Date object
* such that the time and date of the Date object will appear
* to be that of the timezone that you wish to display;
* however, the timezone of the Date returned will be that
* of the client's local time.
*
* A Date object is returned so that you can pass it into whatever
* existing Date parsing code that you use, so be aware that
* if you display the timezone of this Date object, it will most
* likely be incorrect.
*/
function getForeignDate() {
now = new Date();
minutes = now.getTimezoneOffset();
hours = minutes / -60;
hoursDifference = hours - DESIRED_OFFSET;
millisDifference = MILLIS_PER_HOUR * hoursDifference;
millisNow = now.getTime() - millisDifference;
dateInForeignPlace = new Date(millisNow);
return dateInForeignPlace;
}