php sample code analysis to determine whether remote resources exist
<?php $url1='http://www.91hi.net/web/demo/1.jpg' //exists $url2='http://91hi.net/web/demo/www/jd/image/logo.png'; //not exists $get1=get_headers($url1); $get2=get_headers($url2); print_r($get1); print_r($get2);
Return result:
Array ( [0] => HTTP/1.1 404 Not Found [1] => Date: Tue, 14 Mar 2017 10:58:00 GMT [2] => Server: Apache [3] => Vary: User-Agent,Accept-Encoding [4] => Connection: close [5] => Content-Type: text/html ) Array ( [0] => HTTP/1.1 200 OK [1] => Date: Tue, 14 Mar 2017 10:58:00 GMT [2] => Server: Apache [3] => Last-Modified: Wed, 09 Nov 2016 08:57:06 GMT [4] => ETag: "2162a05-13f5-540da70f97c80" [5] => Accept-Ranges: bytes [6] => Content-Length: 5109 [7] => Vary: User-Agent [8] => Connection: close [9] => Content-Type: image/png ) 可以看到返回的http状态信息组成的一维数组.且第一个数组单元为响应状态信息.
So, the obtained status code is used to determine the remote Whether the resource exists.
$statusCode=substr($get1[0], 9, 3); if($statusCode == 200 || $statusCode == 304){ echo "It's exists." }else{ echo "It's not exists." }
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