sorting - Can't sort dates with PHP -

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• how sort date array in php 4 answers

i have php array looks this:

$dates = array(); $dates['01-07-2013'] = 'dummy data'; $dates['01-21-2013'] = 'dummy data'; $dates['01-28-2013'] = 'dummy data'; $dates['01-20-2012'] = 'dummy data'; 

when using ksort($dates) it's not sorting them correctly. there way sort keys this?

i expect sort return:

'01-30-2012', '01-07-2013', '01-21-2013', '01-28-2013', 

those aren't dates, far php concerned. they're strings, it's applying standard string sorting rules it.

you'll need define custom sort function use usort(), or convert dates format sortable string, e.g.

yyyy-mm-dd