Here is an example output: http://larve.net/2006/08/php-http-caching/demo.php?expirein=2%20hours
00001 <?php 00002 require('HttpCaching.php'); 00003 00004 define("DEFAULT", "1 day"); 00005 00006 $howlong = $_GET['expirein']; 00007 00008 $hc = new HttpCaching(); 00009 $hc->ccMustRevalidate(true); 00010 $hc->setLastModifiedFromFile(__FILE__); 00011 00012 if ($howlong == "") { 00013 $diag = 'No caching directives requested'; 00014 $hc->freshFor(constant("DEFAULT")); 00015 } else { 00016 try { 00017 $d = $hc->freshFor($howlong); 00018 if ($d >= 0) { 00019 $diag = "Caching header set to cache for '$howlong', i.e. declared fresh until ". 00020 HttpCaching::formatDate(time() + $d); 00021 } else { 00022 $diag = "No expiry data sent back in HTTP headers"; 00023 } 00024 } catch(Exception $e) { 00025 $diag = $e->getMessage(); 00026 $hc->freshFor(constant("DEFAULT")); 00027 } 00028 } 00029 00030 $hc->sendStatusAndHeaders(true); 00031 ?> 00032 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 00033 <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"> 00034 <head> 00035 <title>HttpCaching demonstration</title> 00036 </head> 00037 <body> 00038 <p> 00039 <?php 00040 print $diag; 00041 ?> 00042 </p> 00043 <hr /> 00044 <p>See <a href="./">HttpCaching home page</a> for details.</p> 00045 </body> 00046 </html>