php - date() expects parameter 2 to be integer, string given

my laravel 5.2 code

$this->timestamp=date('y-m-d',intval($timestamp)); $datetime=date('y/m/d', $timestamp);

date() expects parameter 2 integer, string given

that error occur. error show when choose day 31, not on other days (1 30). other days ok.

when change code that

$this->timestamp=date('y-m-d',intval($timestamp)); $datetime=date('y/m/d', intval($timestamp));

error solved date show not correct. date show 1970/01/01 please me, how fix this?

since you're using laravel, can carbon:

carbon::parse($timestamp)->format('y-m-d');

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