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(PHP 4, PHP 5)

prev — Rewind the internal array pointer

Description

mixed prev ( array &$array )

Returns the array value in the previous place that's pointed to by the internal array pointer, or FALSE if there are no more elements.

Warning

這個函數可能回傳布林值 FALSE,但也可能回傳一個同於 FALSE 的非布林值,像是0或 ""請參考Booleans此節有更多資訊。使用 === 運算子來測試這個函數的回傳值。

Note: You won't be able to distinguish the beginning of an array from a boolean FALSE element. To properly traverse an array which may contain FALSE elements, see the each() function.

prev() behaves just like next(), except it rewinds the internal array pointer one place instead of advancing it.

Example#1 Example use of prev() and friends

<?php
$transport 
= array('foot''bike''car''plane');
$mode current($transport); // $mode = 'foot';
$mode next($transport);    // $mode = 'bike';
$mode next($transport);    // $mode = 'car';
$mode prev($transport);    // $mode = 'bike';
$mode end($transport);     // $mode = 'plane';
?>

See also current(), end(), next(), reset(), and each().