


PHP implements a method to determine whether a page or image has been compressed by gzip
The following editor will bring you a PHP method to determine whether a page or image has been compressed by gzip. The editor thinks it’s pretty good, so I’ll share it with you now and give it as a reference. Let’s follow the editor and take a look
Use php to determine whether the page or image has been compressed by gzip
1. Use get_headers
Page content
<?php ob_start('ob_gzhandler'); // 开启gzip,屏蔽则关闭 $data = array( array('name'=>'one','value'=>1), array('name'=>'two','value'=>2), array('name'=>'three','value'=>3) ); header('content-type:application/json'); echo json_encode($data); ?>
Use get_headers to determine whether to use gzip compression
<?php $url = 'http://www.example.com/'; var_dump(check_gzip($url)); /** * 判断url是否经过gzip压缩 * @param String $url 来源 * @param Boolean */ function check_gzip($url){ $header = get_headers($url, 1); if(isset($header['Vary']) && $header['Vary']=='Accept-Encoding'){ return true; } return false; } ?>
Test results:
When ob_gzhandler is added, true is returned, false is returned after deletion
2. Use curl
Picture
<?php header('content-type:image/jpeg'); ob_start('ob_gzhandler'); // 开启gzip,屏蔽则关闭 echo file_get_contents('test.jpg'); ?>
Use curl to determine whether to use gzip compression
<?php $url = 'http://www.example.com/'; var_dump(check_gzip($url)); /** * 判断url是否经过gzip压缩 * @param String $url 来源 * @param Boolean */ function check_gzip($url){ $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, $url); curl_setopt($ch, CURLOPT_HEADER, 1); // 输出header信息 curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); // 返回的信息不直接输出 curl_setopt($ch, CURLOPT_ENCODING, ''); // 不限制编码类型 $response = curl_exec($ch); if(!curl_errno($ch)){ $info = curl_getinfo($ch); // 获取header $header_size = $info['header_size']; $header_str = substr($response, 0, $header_size); $filter = array("\r\n", "\r"); $header_str = str_replace($filter, PHP_EOL, $header_str); // 检查content-encoding preg_match('/Content-Encoding: (.*)\s/i', $header_str, $matches); if(isset($matches[1]) && $matches[1]=='gzip'){ return true; } } return false; } ?>
Test results:
When ob_gzhandler is added, true is returned, false is returned after deletion
The above is the entire content of this article, I hope it will be helpful to everyone’s study.
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