为什么会有所不同？

Question

echo date("w",strtotime(date("Y-m-d")));
echo date("w",strtotime(date("Y年m月d日")));

Save it as utf8.You'll see the second is bigger than the first one.

Answer 1

Mask,

most probably because strtotime is not able to parse properly the japanese formated date.

In my opinion, by reading the documentation it would accept date formated with - but that's not explicitly said.

trying var_dump(strtotime(date("Y年m月d日")); give false so like in the documentation the strtotime seems to fail to parse it.

so date apply on false which don't give the same result.