我有这个数组：
Array => (
[0] => Array(
[a] => hello,
[b] => world
),
[1] => Array(
[a] => bye,
[b] => planet
),
.....
)
我需要一个函数来将其分类为：
Array => (
[0] => Array(
[a] => bye,
[b] => planet
),
[1] => Array(
[a] => hello,
[b] => world
),
.....
)
试了好几个小时，我都快疯了，请帮帮我。
谢谢！！
如果你想根据数组中所有字符串的内容对数组进行排序，你必须对排序应用一些逻辑。使用usort可以传入任意函数来执行比较。
usort($my_array, function ($a, $b) {
return strcasecmp(implode($a), implode($b));
});
这样，它将比较两个数组，如下所示：
array 1 = [ 'foo', 'bar' ]
array 2 = [ 'baz', 'quux' ]
array 1 is converted to "foobar"
array 2 converted to "bazquux"
compare strings "foobar" to "bazquux"
-> "bazquux" comes first alphabetically, so strcasecmp() return positive integer
-> usort receives the positive integer which informs its sorting algorithm
您可以使用array_reverse（）。PHP有许多内置的数组函数。http://php.net/manual/en/ref.array.php
$test = Array (
0 => Array(
'a' => 'hello',
'b' => 'world'
),
1 => Array(
'a' => 'bye',
'b' => 'planet'
),
);
$reverse = array_reverse($test);
print_r($reverse);
Array (
[0] => Array (
[a] => bye
[b] => planet
)
[1] => Array (
[a] => hello
[b] => world
)
)