Extracting Usable Info From datetime field in php/MySQL

I am trying to format a datetime variable with the following code:

$passed_time = $stu_quiz->c_date_time;
$passed_time_string = date_format($passed_time, 'M-d-Y');

For some reason, if I print $passed_time_string, the output is blank, but if I print out $passed_time, I get the date (in the format开发者_StackOverflow 2011-06-15 21:43:09).

Why is the date_format method not working?

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The date_format function expects a "DateTime" object that is created using date_create.

Example:

$passed_time = date_create($stu_quiz->c_date_time);
$passed_time_string = date_format($passed_time, 'M-d-Y');

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You are looking for just date() http://php.net/manual/en/function.date.php

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If you don't have PHP 5.3 and cannot use the DateTime class, try this:

$passed_time_string = date("M-d-Y", strtotime($passed_time));

First it converts your original MySQL time to a unix timestamp, then formats it as M-d-Y