【下载文档:  php使用gzip压缩传输js和css文件的方法.txt 】

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php使用gzip压缩传输js和css文件的方法
本文实例讲述了php使用gzip压缩传输js和css文件的方法。分享给大家供大家参考。具体如下：
/**
* 完整调用示例:
* 1、combine.php?t=j&b=public&fs=jslib.jquery,function
*
* 该例子调用的是网站根目录下的public/jslib/jquery.js和public/function.js
*
* 2、combine.php?t=j&fs=jslib.jquery,function
*
* 该例子调用的是网站根目录下的jslib/jquery.js和function.js
*
* 3、combine.php?t=c&b=public.css&fs=common,index
*
* 该例子调用的是网站根目录下的public/css/common.css和public/css/index.css
*
* 4、combine.php?t=c&fs=css.common
* 该例子调用的是网站根目录下的css/common.css
*
* 注:多个文件名之间用,分隔;只有一个文件名最后不要有,
* 用,分隔的多个文件会被压缩进一个文件，一次性传给浏览器
**/
$is_bad_request=false;
$cache = true;
$doc_root_uri=$_SERVER['DOCUMENT_ROOT'].'/';
$cachedir = $doc_root_uri . 'public/cache';
//文件类型，j为js，c为css
$type=isset($_GET['t'])?($_GET['t']=='j'||$_GET['t']=='c'?$_GET['t']:''):'';
//存放js和css文件的基目录, 例如:?b=public.js 代表的是/public/js文件夹，出发点是网站根目录
//基目录参数不是必须的，如果有基目录那么这个基目录就会附加在文件名之前
$base =isset($_GET['b'])?($doc_root_uri.str_replace('.','/',$_GET['b'])):$doc_root_uri;
//文件名列表，文件名不带后缀名.比如基目录是
//文件名的格式是 :基目录(如果有)+文件包名+文件名
//例如:类型是j,
// 文件名public.js.jquery
// 如果有基路径且为public，
// 那么转换后的文件名就是/public/public/js/jquery.js
// 如果没有基路径
// 那么转换后的文件名就是/public/js/jquery.js
//多个文件名之间用,分隔
$fs=isset($_GET['fs'])?str_replace('.','/',$_GET['fs']):'';
$fs=str_replace(',','.'.($type=='j'?'js,':'css,'),$fs);
$fs=$fs.($type=='j'?'.js':'.css');
if($type==''||$fs==''){$is_bad_request=true;}
//die($base);
if($is_bad_request){header ("HTTP/1.0 503 Not Implemented");}
$file_type=$type=='j'?'javascript':'css';
$elements = explode(',',preg_replace('/([^?]*).*/', '\1', $fs));
// Determine last modification date of the files
$lastmodified = 0;
while (list(,$element) = each($elements)) {
$path =$base . '/' . $element;
if (($type == 'j' && substr($path, -3) != '.js') ||
($type == 'c' && substr($path, -4) != '.css')) {
header ("HTTP/1.0 403 Forbidden");
exit;
}
if (substr($path, 0, strlen($base)) != $base || !file_exists($path)) {
header ("HTTP/1.0 404 Not Found");
exit;
}
$lastmodified = max($lastmodified, filemtime($path));
}
// Send Etag hash
$hash = $lastmodified . '-' . md5($fs);
header ("Etag: \"" . $hash . "\"");
if (isset($_SERVER['HTTP_IF_NONE_MATCH']) &&
stripslashes($_SERVER['HTTP_IF_NONE_MATCH']) == '"' . $hash . '"')
{
// Return visit and no modifications, so do not send anything
header ("HTTP/1.0 304 Not Modified");
header ("Content-Type: text/" . $file_type);
header ('Content-Length: 0');
}
else
{
// First time visit or files were modified
if ($cache)
{
// Determine supported compression method
$gzip = strstr($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip');
$deflate = strstr($_SERVER['HTTP_ACCEPT_ENCODING'], 'deflate');
// Determine used compression method
$encoding = $gzip ? 'gzip' : ($deflate ? 'deflate' : 'none');
// Check for buggy versions of Internet Explorer
if (!strstr($_SERVER['HTTP_USER_AGENT'], 'Opera') &&
preg_match('/^Mozilla\/4\.0 \(compatible; MSIE ([0-9]\.[0-9])/i', $_SERVER['HTTP_USER_AGENT'], $matches)) {
$version = floatval($matches[1]);
if ($version < 6)
$encoding = 'none';
if ($version == 6 && !strstr($_SERVER['HTTP_USER_AGENT'], 'EV1'))
$encoding = 'none';
}
// Try the cache first to see if the combined files were already generated
$cachefile = 'cache-' . $hash . '.' . $file_type . ($encoding != 'none' ? '.' . $encoding : '');
if (file_exists($cachedir . '/' . $cachefile)) {
if ($fp = fopen($cachedir . '/' . $cachefile, 'rb')) {
if ($encoding != 'none') {
header ("Content-Encoding: " . $encoding);
}
header ("Content-Type: text/" . $file_type);
header ("Content-Length: " . filesize($cachedir . '/' . $cachefile));
fpassthru($fp);
fclose($fp);
exit;
}
}
}
// Get contents of the files
$contents = '';
reset($elements);
while (list(,$element) = each($elements)) {
$path = $base . '/' . $element;
$contents .= "\n\n" . file_get_contents($path);
}
// Send Content-Type
header ("Content-Type: text/" . $file_type);
if (isset($encoding) && $encoding != 'none')
{
// Send compressed contents
$contents = gzencode($contents, 9, $gzip ? FORCE_GZIP : FORCE_DEFLATE);
header ("Content-Encoding: " . $encoding);
header ('Content-Length: ' . strlen($contents));
echo $contents;
}
else
{
// Send regular contents
header ('Content-Length: ' . strlen($contents));
echo $contents;
}
// Store cache
if ($cache) {
if ($fp = fopen($cachedir . '/' . $cachefile, 'wb')) {
fwrite($fp, $contents);
fclose($fp);
}
}
}
希望本文所述对大家的php程序设计有所帮助。