array_reverse()函数是 PHP 的内置函数。 array_reverse( ) 函数用于反转数组中元素的顺序。此函数是在 PHP 4.0 中引入的。
语法
array array_reverse ( array $array [, bool $preserve_keys = FALSE ] ); 参数
| 参数 | 描述 | 必须/可选 |
|---|---|---|
| array | 指定一个数组 | 必须 |
| preserve_keys | 指定 TRUE 或 FALSE 函数是否保留数组的键。默认值为 FALSE。 | 可选 |
返回值
array_reverse() 函数返回反转的数组。
例子1
<?php
$a = array("yxjc123", 2.0, array("PHP", "JAVA"));
$reversed = array_reverse($a);
$preserved = array_reverse($a, true);
print_r($a);
print_r($reversed);
print_r($preserved);
?> 输出:
Array ( [0] => yxjc123 [1] => 2 [2] => Array ( [0] => PHP [1] => JAVA ) ) Array ( [0] => Array ( [0] => PHP [1] => JAVA )
[1] => 2 [2] => yxjc123 ) Array ( [2] => Array ( [0] => PHP [1] => JAVA ) [1] => 2 [0] => yxjc123 )
[1] => 2 [2] => yxjc123 ) Array ( [2] => Array ( [0] => PHP [1] => JAVA ) [1] => 2 [0] => yxjc123 )
例子2
<?php
$num= array(100,200,300,400,500);
$x = array_reverse($num,true);
$y = array_reverse($num);
print_r($x);
print_r($y);
?> 输出:
Array ([4] => 500 [3] => 400 [2] => 300 [1] => 200 [0] => 100) Array ([0] => 500 [1] => 400 [2] => 300 [3] => 200 [4] => 100)
例子3
<?php
$lang = array("a"=>"PHP","b"=>"JAVA","c"=>"PYTHON");
print_r(array_reverse($lang));
?> 输出:
Array ( [c] => PYTHON [b] => JAVA [a] => PHP )
例子4
<?php
function Reverse($array)
{
return(array_reverse($array, true));
}
$lang = array("PHP", "JAVA", "PERL", "PYTHON");
print_r($lang);
print_r(Reverse($lang));
?> 输出:
Array ( [0] => PHP [1] => JAVA [2] => PERL [3] => PYTHON ) Array ( [3] => PYTHON [2] => PERL [1] => JAVA [0] => PHP )