(PECL apcu >= 4.0.0)
apcu_exists — 检查条目是否存在
范例 #1 apcu_exists() 范例
<?php
$fruit = 'apple';
$veggie = 'carrot';
apcu_store('foo', $fruit);
apcu_store('bar', $veggie);
if (apcu_exists('foo')) {
echo "Foo exists: ";
echo apcu_fetch('foo');
} else {
echo "Foo does not exist";
}
echo PHP_EOL;
if (apcu_exists('baz')) {
echo "Baz exists.";
} else {
echo "Baz does not exist";
}
echo PHP_EOL;
$ret = apcu_exists(array('foo', 'donotexist', 'bar'));
var_dump($ret);
?>以上示例将输出类似于以下内容：
Foo exists: apple
Baz does not exist
array(2) {
["foo"]=>
bool(true)
["bar"]=>
bool(true)
}