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array_reverse (PHP 4 , PHP 5) array_reverse --
返回一个单元顺序相反的数组
说明array array_reverse ( array array [, bool preserve_keys])
array_reverse() 接受数组
array 作为输入并返回一个单元为相反顺序的新数组，如果
preserve_keys 为 TRUE 则保留原来的键名。
例子 1. array_reverse() 例子 |
<?php
$input = array ("php", 4.0, array ("green", "red"));
$result = array_reverse ($input);
$result_keyed = array_reverse ($input, TRUE);
?>
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这将使 $result 和
$result_keyed 具有相同的单元，但是注意键名的区别。$result
和 $result_keyed 的打印输出显示分别为：
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Array
(
[0] => Array
(
[0] => green
[1] => red
)
[1] => 4
[2] => php
)
Array
(
[2] => Array
(
[0] => green
[1] => red
)
[1] => 4
[0] => php
)
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注:
第二个参数是 PHP 4.0.3 中新加的。
参见 array_flip()。
david at audiogalaxy dot com
04-Mar-2000 04:40
With associative arrays array_reverse() keeps key => value pairs matched
but reverses the order of the array as spaned by functions like each().
With numerical indexes array_reverse not only reverses position (as spaned
by each) but also renumbers the keys.
Both cases seem to be what
people would generally want: indeed without the renumbering behavior,
someone refering to array elements by numerical key wouldn't think
array_reverse did anything.
However, people who are trying to keep
numerical keys associated with their values - e.g. trying to have holes in
their arrays - will be foiled by the renumbering. The most telling results
come from applying array_reverse() to arrays with mixed keys (some numbers
and some strings). The strings stay attached and the rest of the keys get
renumbered around them - most annoying if you are thinking what you've got
is an associative array but some of your keys happen to be numbers.
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array_reduce
