


Why is `-new Date().getTimezoneOffset()/60` an outdated approach to time zone detection?
Understanding Time Zone Detection
Detecting a user's time zone plays a crucial role in customizing web applications to local time preferences. This article explores the various approaches to achieve time zone detection, specifically addressing the confusion surrounding the syntax -new Date().getTimezoneOffset()/60.
Determining Timezone via Browser
One popular method involves leveraging the browser's built-in functionality. By utilizing libraries such as jstimezonedetect, you can determine the client's time zone directly from the browser. The jstz.determine() function returns an object containing the detected time zone, which you can then process on the server side.
Example Code:
<code class="javascript">$(document).ready(function(){ var tz = jstz.determine(); // Determines the time zone of the browser client var timezone = tz.name(); //For e.g.:"Asia/Kolkata" for the Indian Time. $.post("url-to-function-that-handles-time-zone", {tz: timezone}, function(data) { //Preocess the timezone in the controller function and get //the confirmation value here. On success, refresh the page. }); });</code>
Understanding -new Date().getTimezoneOffset()/60
This syntax represents an outdated approach to time zone detection. The getTimezoneOffset() method returns the number of minutes between the local time and UTC (Coordinated Universal Time). Dividing this value by 60 yields the time zone offset in hours. However, this method has limitations as it assumes the user's time zone is correctly set in the browser and does not account for daylight saving time.
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