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NathanielInman/jsDateNeedsFixed.txt

Last active March 20, 2017 16:29
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Javascript new Date() in local time is wrong and how to fix
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jsDateNeedsFixed.txt
new Date('2017-02-20').getDay()
=> 0 // February 20th of 2017 is a MONDAY not SUNDAY!!!
new Date('2017-02-20')
=> Sun Feb 19 2017 18:00:00 GMT-0600 (CST) //hmm... so its converting to local time?
new Date('2017-02-20 00:00:00')
=> Mon Feb 20 2017 00:00:00 GMT-0600 (CST) //aha! it is, so how do we fix it?
new Date(new Date('2017-02-20').getTime() + (new Date('2017-02-20').getTimezoneOffset() * 60000))
=> Mon Feb 20 2017 00:00:00 GMT-0600 (CST) //yay! But that's too long...
new Date(new Date('2017-02-20').toUTCString().substr(0, 25))
=> Mon Feb 20 2017 00:00:00 GMT-0600 (CST) //much better
new Date(new Date('2017-02-20').toUTCString().substr(0, 25)).getDay()
=> 1 // Finally. Seriously, they should adjust the Date object
new Date('2017-02-20').getUTCDay()
=> 1 // oh... (^_^)
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For more information: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getUTCDay

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