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'nTicks' = number of milliseconds since midnight of January 1, 1970 The following takes care of all the complexities of date and time formats on the client computer: function formatDateTimeFromTicks(nTicks) Then what you'd generally need is to format date/time for the end-user for their local timezone and format. ![]() Return tmLoc.getTime() + tmLoc.getTimezoneOffset() * 60000 The offset is in minutes - convert it to ms = number of milliseconds between current UTC time and midnight of January 1, 1970 To get the current UTC time: function getCurrentTimeUTC() JAVASCRIPT GET CURRENT UTC TIME CODEHere's a little JavaScript code that I use. As a rule I try to store and work with UTC dates, in the form of ticks or " number of milliseconds since midnight of January 1, 1970." This really simplifies storage, sorting, calculation of offsets, and most of all, rids you of the headache of the "Daylight Saving Time" adjustments. You generally don't need to do much of "Timezone manipulation" on the client side. So, in short, the reason there isn't a lot of native support for time zone manipulation is because you simply don't want to be doing it. On the downside there is not a lot of scope for forcing the time zone or locale for the client (that I am aware of), which can be annoying for website-specific settings, but I guess the reasoning behind this is that it's a user configuration that shouldn't be touched. It's good practice to convert to UTC as soon as you can, and the js Date object makes this fairly trivial. All the local time manipulations allow you to display something sensible to the user and to convert strings from user input. The local time values exist purely for the benefit of the user, and date values by default display in their local time. What this means for you as a developer is that you never have to deal with local time conversions yourself. You can't be confused about what a date string means if you include the date offset. Or if you would rather work with a millisecond timestamp (number of milliseconds from the 1st January 1970 UTC) someDate.getTime() When you want to pass the Date value back to the server you would call someDate.toISOString() So you can infer the exact UTC time this way. JAVASCRIPT GET CURRENT UTC TIME ISOUsing something like iso8601.js solves this varying behaviour by defining a single implementation of the Date object.īy default, the spec says you can create dates with an extended ISO 8601 date format like var someDate = new Date('T12:00Z') JAVASCRIPT GET CURRENT UTC TIME TRIALMy biggest complaint about the Date object is the amount of undefined behaviour that browser implementers have chosen to include, which can confuse people who attack dates in js with trial and error than reading the spec. In js, all Date values have an underlying UTC value which is passed around and known regardless of the offest or time zone conversions that you do. The C# DateTime objects have a Kind property, but no strict underlying time zone as such, and time zone conversions are difficult to track if you are converting between two non UTC and non local times. I actually think Date values in js are far better than say the C# DateTime objects. This is because getUTCDate() returns the day of the month whereas, getUTCDay() returns the day of the week. "Sun, 03:50:34 GMT" // four hours less than my local time, and two hours less than the original time - because my GMT+2 input was interpreted as GMT+0!Īlso note that getUTCDate() cannot be substituted for getUTCDay(). > var d2 = new Date( d1.getUTCFullYear(), d1.getUTCMonth(), d1.getUTCDate(), d1.getUTCHours(), d1.getUTCMinutes(), d1.getUTCSeconds() ) "Sun, 05:50:34 GMT" // two hours less than my local time Observe (I'm in GMT +02:00 right now, and it's 07:50): > var d1 = new Date() If UTC time is passed in, the results will differ. For a string representation, David Ellis' answer works. ![]() It will factor the current timezone offset into the result. Note that getTime() returns milliseconds, not plain seconds.įor a UTC/Unix timestamp, the following should suffice: Math.floor((new Date()).getTime() / 1000) JAVASCRIPT GET CURRENT UTC TIME ANDROID(I had problems getting that to work in an older Android browser.) To set the timezone of a certain date object is to construct it from a date string that includes the timezone. Dates constructed that way use the local timezone, making the constructed date incorrect. ![]()
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