将秒数转换成时分秒
gmstrftime('%H:%M:%S', $time);
计算二维数组($arr)下标值相同(response_num)的数据和
array_sum(array_map(function ($val) {
return $val['response_num'];
}, $arr));
运算结果:2
array_column($arr,‘键名’)取出二维数组中指定列组成新数组
$a = array(
array(
'id' => 5698,
'first_name' => 'Bill',
'last_name' => 'Gates',
),
array(
'id' => 4767,
'first_name' => 'Steve',
'last_name' => 'Jobs',
),
array(
'id' => 3809,
'first_name' => 'Mark',
'last_name' => 'Zuckerberg',
)
);
$last_names = array_column($a, 'last_name');
print_r($last_names);
结果:
Array
(
[0] => Gates
[1] => Jobs
[2] => Zuckerberg
)