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(PECL apcu >= 4.0.0)
apcu_exists — Checks if entry exists
$keys
)Checks if one or more APCu entries exist.
keys
A string , or an array of strings, that contain keys.
Returns TRUE
if the key exists, otherwise FALSE
Or if an
array was passed to keys
, then
an array is returned that contains all existing keys, or an empty
array if none exist.
Example #1 apcu_exists() example
<?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 );
?>
以上例程的输出类似于:
Foo exists: apple Baz does not exist array(2) { ["foo"]=> bool(true) ["bar"]=> bool(true) }