php获取远程图片体积大小的实例
有时候，我们需要知道远程图片的体积大小，那么PHP如何可以做到呢？
直接看代码吧，很好明白的，代码如下:
- //用法 echo remote_filesize($url,$user='',$pw='');
- $url = "http://www.aa.com/librarys/images/random/rand_11.jpg";//这里要换成你的图片地址
- echo remote_filesize($url,$user='',$pw='');
- function remote_filesize($uri,$user='',$pw='')
- {
- // start output buffering
- ob_start();
- // initialize curl with given uri
- $ch = curl_init($uri); // make sure we get the header
- curl_setopt($ch, CURLOPT_HEADER, 1); // make it a http HEAD request
- curl_setopt($ch, CURLOPT_NOBODY, 1); // if auth is needed, do it here
- if (!emptyempty($user) && !emptyempty($pw))
- {
- $headers = array('Authorization: Basic ' . base64_encode($user.':'.$pw));
- curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
- }
- $okay = curl_exec($ch);
- curl_close($ch); // get the output buffer
- $head = ob_get_contents(); // clean the output buffer and return to previous // buffer settings
- ob_end_clean(); // gets you the numeric value from the Content-Length // field in the http header
- $regex = '/Content-Length:\s([0-9].+?)\s/';
- $count = preg_match($regex, $head, $matches); // if there was a Content-Length field, its value // will now be in $matches[1]
- if (isset($matches[1]))
- {
- $size = $matches[1];
- } //phpfensi.com
- else
- {
- $size = 'unknown';
- }
- $last_mb = round($size/(1024*1024),3);
- $last_kb = round($size/1024,3);
- return $last_kb . 'KB / ' . $last_mb.' MB';
- }
函数的思路是，先CURL获取图片到缓冲区，然后正则获取图片的Content-Length信息就OK了。