Name
isCached() — returns true if there is a valid cache for this template
Description
bool isCached(string template,
string cache_id,
string compile_id);This only works if
$cachingis set to one ofSmarty::CACHING_LIFETIME_CURRENTorSmarty::CACHING_LIFETIME_SAVEDto enable caching. See the caching section for more info.You can also pass a
$cache_idas an optional second parameter in case you want multiple caches for the given template.You can supply a
$compile idas an optional third parameter. If you omit that parameter the persistent$compile_idis used if its set.If you do not want to pass a
$cache_idbut want to pass a$compile_idyou have to passNULLas a$cache_id.
Technical Note
If isCached() returns TRUE it actually loads the
cached output and stores it internally. Any subsequent call to
display() or
fetch()
will return this internally stored output and does not try to reload
the cache file. This prevents a race condition that may occur when a
second process clears the cache between the calls to
isCached() and to
display()
in the example above. This also means calls to
clearCache()
and other changes of the cache-settings may have no effect after
isCached() returned TRUE.
Пример 14.32. isCached()
<?php
$smarty->setCaching(Smarty::CACHING_LIFETIME_CURRENT);
if(!$smarty->isCached('index.tpl')) {
// do database calls, assign vars here
}
$smarty->display('index.tpl');
?>
Пример 14.33. isCached() with multiple-cache template
<?php
$smarty->setCaching(Smarty::CACHING_LIFETIME_CURRENT);
if(!$smarty->isCached('index.tpl', 'FrontPage')) {
// do database calls, assign vars here
}
$smarty->display('index.tpl', 'FrontPage');
?>
See also
clearCache(),
clearAllCache(),
and
caching section.