Static php page notes

Static php page notes,

 Output_buffering: on * Several cache functions: ob_start (); ob_clean (); ob_get_content (); ob_end_clean (); Disable Cache and clear * ob_flush (); outputs and clears the content in the cache, but does not close ob_end_flush (); closes and outputs * // **/ob_start (); // enables the cache echo 'yyy '; // If cache is not enabled, an error is reported. If no header is encountered, php sends a header by default. this header cannot be modified ('content-type: text/htm; charset = utf-8 '); echo '000000'; ob_get_contents (); // Get the cached content ob_end_clean (); echo 'AA '; // put the header in the program cache ('content-type: text/htm; charset = utf-8 '); // An error is reported during running, because the cache has been disabled/** use the cache mechanism provided by php to make a real cache * the content of the truly cached page should not be changed for a long time, in addition, different users see the same thing * principle: when the user first accesses the database, he queries the database and obtains the content in the cache area, and put it in the cache file ** // ***/ob_start (); // The slow-saving file contains $html_filename='static.html '; if (file_exists ($ html_filename) & (filemtime ($ html_filename) + 30)> time () // regenerate after 30 seconds {// Retrieve the cached page content echo file_get_contents ($ html_filename); exit ;} echo 'Ur content'{html_content}ob_get_contents({$html_filename}'static.html '; file_put_contents ($ html_filename, $ html_content);/*** defects of the above principles: 1. insufficient real-time performance 2. not conducive to seo * solution: Update the cache file when the database is added or updated */if ($ _ REQUEST ['AC'] = 'ADD ') // update is also {// Obtain the template file $ template_content = file_get_contents ('Template. tpl '); // replace the tag $ php_content = str_replace ("{",'
 ', $ Template_content); // Generate the cache file $ php_tplname = 'php _ tpl. php '; file_put_contents ($ php_tplname, $ php_content); include (file_put_contents); $ html_content = metadata (); comment'; file_put_contents ($ html_filename, $ html_content );} /*** real static defect: many cached files are generated, which occupy the hard disk * for massive html generation, you can consider using pseudo static files */$ str = '2017, 123 '; preg_match ('/\ d/is', $ str, $ arr ); // Match four consecutive numbers and return to arr. it only matches an arr [0] preg_match ('/ (\ D)/is ', $ str, $ arr); // at this time, arr returns three strings where 0 matches, arr [n] returns the matched string in order of expression // use the preg_match_all () function for all matching requests; note: to enable the rewrite module in apache configuration, you must also set the permission for derecloud allowoverride from all. htacss // the matching rule is top-down. you can set the error page * RewireEngine On * news-id (\ d )\. html $ news. php? Id = $1 * news-id (\ d).html $ error. php # put the error page to the end */