PHP function: Determine whether the remote file exists instance code_PHP tutorial

This article introduces the PHP function-determine whether the remote file exists instance code

2. /*
3. Function: remote_file_exists
4. Function: Determine whether the remote file exists
5. Parameters: $url_file - Remote file URL
6. Return: returns true if it exists, false if it does not exist or for other reasons
7. */
8. function remote_file_exists($url_file){
9. //Detect input
10. $url_file = trim($url_file);
11. if (empty($url_file)) { return false; }
12. $url_arr = parse_url($url_file);
13. if (!is_array($url_arr) || empty($url_arr )){ return false; }
15. //Get request data
16. $host = $url_arr[host];
17. $path = $url_arr [path] ."?". $url_arr[query];
18. $port = isset($url_arr[port]) ? $url_arr[port] : "80";
20. //Connect to server
21. $fp = fsockopen($host, $port, $err_no, $err_str, 30);
22. if (!$fp){ return false; }
23.                                                                                                                                         "Host: ".$host." ";
24. $request_str .= "Connection: Close ";
26. //Send request
27. fwrite ($fp, $request_str);
28. $first_header = fgets($fp, 1024);
29. fclose($fp);
31. / /Determine whether the file exists
32. if (trim($first_header) == ""){ return false; }
33. if (!preg_match("/200/", $first_header)){
34. return false;
35. }
36. return true;
37. }
39. //Test code
40. $str_url = http://www.ite5e.com/newsinfo.php?nid=1493;
41. $exits = remote_file_exists($str_url);
42. echo $exists ? "Exists" : "Not exists";
43. ?>

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http: //www.bkjia.com/PHPjc/486160.htmlTechArticleThis article introduces the PHP function - determine whether the remote file exists instance code?php /* Function: remote_file_exists Function: determine the remote file Whether parameters exist: $url_file - remote file URL...