要使用 apcu，必須安裝 apcu 擴充功能。您可以在這裡找到它 https://pecl.php.net/package/APCu
注意：apcu 與 apc 不同！
APCu 是過時 APC 擴充功能的官方替代品。APC 提供了操作碼快取 (opcache) 和物件快取。由於 PHP 5.5 及更高版本包含了自己的 opcache，APC 不再相容，其 opcache 功能變得無用。APC 的開發人員接著建立了 APCu，它只提供物件快取（即「記憶體資料快取」）功能（他們移除了過時的 opcache）。
想知道如何使用 apcu 嗎？以下範例應能讓您有基本的了解。
<?php
date_default_timezone_set('Europe/Amsterdam');
$apcuAvailabe = function_exists('apcu_enabled') && apcu_enabled();
if($apcuAvailabe)
{
//apcu_clear_cache();
$test1 = apcu_fetch('test1');
$test2 = apcu_fetch('test2');
}
$test1[] = rand(1, 1000);
$test2[] = rand(1, 1000);
if($apcuAvailabe)
{
apcu_store('test1', $test1);
apcu_store('test2', $test2);
}
echo sprintf('current - value = %s<br/>', implode(' ,', $test1));
echo sprintf('current - value = %s<br/>', implode(' ,', $test2));
$aPCUIterator = new APCUIterator();
echo sprintf('totalCount = %s<br/>', $aPCUIterator->getTotalCount());
//echo sprintf('totalHits = %s<br/>', $aPCUIterator->getTotalHits()); // Not implemneted/available?
echo sprintf('totalSize = %s<br/>', $aPCUIterator->getTotalSize());
echo '----------------------------------<br/>';
$aPCUIterator->rewind();
echo sprintf('key = %s<br/>', $aPCUIterator->key());
echoCurrent($aPCUIterator->current());
$aPCUIterator->next();
echo '----------------------------------<br/>';
echo sprintf('key = %s<br/>', $aPCUIterator->key());
echoCurrent($aPCUIterator->current());
echo sprintf('valid = %s<br/>', $aPCUIterator->valid() ? 'true' : 'false');
function echoCurrent($current)
{
echo sprintf('current - type = %s<br/>', $current['type']);
echo sprintf('current - key = %s<br/>', $current['key']);
echo sprintf('current - value = %s<br/>', implode(' ,', $current['value']));
//echo sprintf('current - num_hits = %s<br/>', $current['num_hits']); // Not implemneted/available?
echo sprintf('current - mtime = %s<br/>', date("d-m-Y H:i:s", $current['mtime']));
echo sprintf('current - creation_time = %s<br/>', date("d-m-Y H:i:s", $current['creation_time']));
echo sprintf('current - deletion_time = %s<br/>', date("d-m-Y H:i:s", $current['deletion_time']));
echo sprintf('current - access_time = %s<br/>', date("d-m-Y H:i:s", $current['access_time']));
//echo sprintf('current - ref_count = %s<br/>', $current['ref_count']); // Not implemneted/available?
echo sprintf('current - mem_size = %s<br/>', $current['mem_size']);
//echo sprintf('current - ttl = %s<br/>', $current['ttl']); // Not implemneted/available?
}
?>