bool is_cached ( string template [, string cache_id [, string compile_id]])
This returns TRUE if there is a valid cache for this template.
This only works if caching is set to true.
Example 1. is_cached
<?php
$smarty->caching = true;
if(!$smarty->is_cached("index.tpl")) {
// do database calls, assign vars here
}
$smarty->display("index.tpl");
?>
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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 you do not want to pass a cache id but want to pass a compile
id you have to pass null as cache id.
Example 2. is_cached with multiple-cache template
<?php
$smarty->caching = true;
if(!$smarty->is_cached("index.tpl", "FrontPage")) {
// do database calls, assign vars here
}
$smarty->display("index.tpl", "FrontPage");
?>
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Technical Note:
If is_cached 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 is_cached and to
display in the example above. This also means calls to
clear_cache()
and other changes of the cache-settings may have no effect after
is_cached returned true.
