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HomeBackend DevelopmentPHP Tutorialphp数组函数序列之rsort() - 对数组的元素值进行降序排序_php技巧

rsort()定义和用法
rsort() 函数对数组的元素按照键值进行逆向排序。与 arsort() 的功能基本相同。

注释:该函数为 array 中的单元赋予新的键名。这将删除原有的键名而不仅是重新排序。

如果成功则返回 TRUE,否则返回 FALSE。

可选的第二个参数包含另外的排序标志。

语法
rsort(array,sorttype)参数 描述
array 必需。输入的数组。
sorttype 可选。规定如何排列数组的值。可能的值:

SORT_REGULAR - 默认。以它们原来的类型进行处理(不改变类型)。
SORT_NUMERIC - 把值作为数字来处理
SORT_STRING - 把值作为字符串来处理
SORT_LOCALE_STRING - 把值作为字符串来处理,基于本地设置*。

*:该值是 PHP 4.4.0 和 5.0.2 新加的。在 PHP 6 之前,使用了系统的区域设置,可以用 setlocale() 来改变。自 PHP 6 起,必须用 i18n_loc_set_default() 函数。

例子
复制代码 代码如下:

$my_array = array("a" => "Dog", "b" => "Cat", "c" => "Horse");
rsort($my_array);
print_r($my_array);
?>

输出:
Array
(
[0] => Horse
[1] => Dog
[2] => Cat
)
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