Name

isCached() - returns true if there is a valid cache for this template

说明

bool isCached(string template,
string cache_id,
string compile_id);
  • This only works if $caching is set to one of Smarty::CACHING_LIFETIME_CURRENT or Smarty::CACHING_LIFETIME_SAVED to enable caching. See the caching section for more info.

  • You can also pass a $cache_id as an optional second parameter in case you want multiple caches for the given template.

  • You can supply a $compile id as an optional third parameter. If you omit that parameter the persistent $compile_id is used if its set.

  • If you do not want to pass a $cache_id but want to pass a $compile_id you have to pass NULL as 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.

Example 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');
?>

   

Example 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.