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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

本函式可能回傳布林值 FALSE,但也可能回傳一個與 FALSE 等值的非布林值,例如 0 或者 ""。請參閱布林類型章節以獲取更多訊息。應使用 === 運算符來測試本函式的回傳值。

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().