?
This document uses PHP Chinese website manual Release
You can have multiple cache files for a single call to display() or
fetch(). Let's say that a call to display('index.tpl') may have several
different output contents depending on some condition, and you want
separate caches for each one. You can do this by passing a cache_id as the
second parameter to the function call.
你可以用單個(gè)函數(shù)display()或fetch()來(lái)輸出多個(gè)緩存文檔。display('index.tpl')在多種條件下會(huì)有不同的輸出內(nèi)容,要單獨(dú)的把緩存分開(kāi)??梢酝ㄟ^(guò)函數(shù)的第二參數(shù)cache_id來(lái)達(dá)到效果。
Example 14-6. passing a cache_id to display()
|
Above, we are passing the variable $my_cache_id to display() as the cache_id.
For each unique value of $my_cache_id, a separate cache will be generated
for index.tpl. In this example, "article_id" was passed in the URL and is
used as the cache_id.
上面,我們通過(guò)變量$my_cache_id作為cache_id來(lái)display()。在index.tpl里$my_cache_id的每個(gè)唯一值,會(huì)建立單獨(dú)的緩存。在這個(gè)例子里,"article_id"在URL傳送,并用作cache_id。
Technical Note: Be very cautious when passing values from a client (web browser) into Smarty (or any PHP application.) Although the above example of using the article_id from the URL looks handy, it could have bad consequences. The cache_id is used to create a directory on the file system, so if the user decided to pass an extremely large value for article_id, or write a script that sends random article_ids at a rapid pace, this could possibly cause problems at the server level. Be sure to sanitize any data passed in before using it. In this instance, maybe you know the article_id has a length of 10 characters and is made up of alpha-numerics only, and must be a valid article_id in the database. Check for this!
技術(shù)提示:要注意從客戶端(web瀏覽器)傳值到Smarty(或任何PHP應(yīng)用程序)的過(guò)程。盡管上面的例子用article_id從URL傳值看起來(lái)很方便,卻可能有糟糕的后果[安全問(wèn)題]。cache_id被用來(lái)在文件系統(tǒng)里創(chuàng)建目錄,如果用戶想為article_id賦一個(gè)很大的值,或?qū)懸恍┐a來(lái)快速發(fā)送隨機(jī)的article_ids,就有可能會(huì)使服務(wù)器出現(xiàn)問(wèn)題。確定在使用它之前清空已存在的數(shù)據(jù)。在這個(gè)例子,可能你知道article_id的長(zhǎng)度(值吧?!)是10字符,并只由字符-數(shù)字組成,在數(shù)據(jù)庫(kù)里是個(gè)可用的article_id。Check for this!要注意檢查這個(gè)問(wèn)題!〔要注意這個(gè)提示!不用再說(shuō)了吧?〕
Be sure to pass the same cache_id as the second parameter to is_cached() and clear_cache().
確定傳給is_cached()和clear_cache()的第二參數(shù)是同一個(gè)cache_id。
Example 14-7. passing a cache_id to is_cached()
|
You can clear all caches for a particular cache_id by passing null as the
first parameter to clear_cache().
你可以通過(guò)把clear_cache()的第一參數(shù)設(shè)為null來(lái)為特定的cache_id清除所有緩存。
Example 14-8. clearing all caches for a particular cache_id
|
In this manner, you can "group" your caches together by giving them the
same cache_id.
通過(guò)這種方式,你可以用相同的cache_id來(lái)把你的緩存集合起來(lái)。