Reputation: 29
When I output a date in php or javascript, how is it calculated? Is it affected by the time a user has set on his computer or is it taken from an external source? If the user can affect it, then how do I make sure my code gets the real date/time?
Upvotes: 1
Views: 119
Reputation: 3820
There is a difference in technology and the context of these technologies. Meaning front-end (client side) or back-end (server side). The difference in PHP
and JavaScript
are on the level of invokement.
PHP
PHP
is run on a dedicated server, not a clients machine. When the time function is invoked from within the PHP
context, the time will be taken from the server side. Meaning the time of the hosting server.
JavaScript
JavaScript
is running at client side level (browser). Time taken within the JavaScript
context will take the clients operating system time. Changing your operating system time settings will have effect on your JavaScript
time fetching.
In this case we are not taking into account any JavaScript
back-end, like NodeJS
. Since this behaves as the above mentioned PHP
context.
Whenever I need to ensure correct Date/Time on a client side JavaScript
application, I'll launch a REST request to retrieve the server time. Counting on the server time takes into account that only authenticated system admin's have control on the server Data/Time settings. And we can rely on this Date/Time truth.
Upvotes: 1
Reputation: 749
Javascript gets it from the users clock
Where does javascript get a new date from
PHP gets it from the Server
Where does PHP get its date information from
Upvotes: 0