PHP function: Determine if a remote file exists instance code _php tutorial

This article describes PHP functions-determining if a remote file has an instance code

4. /*
6. Function: remote_file_exists
8. Function: Determine whether a remote file exists
10. Parameters: $url _file-Remote file URL
12. Return: Presence returns true, no presence or other reason returned false
14. */
16. function remote_file_exists ($url _file) {
18. Detection input
20. $url _file = Trim ($url _file);
22. if (Empty ($url _file)) {return false;}
24. $url _arr = Parse_url ($url _file);
26. if (!is_array ($url _arr) | | empty ($url _arr)) {return false;}
30. GET Request data
32. $host = $url _arr[host];
34. $path = $url _arr[path]. "?". $url _arr[query];
36. $port = Isset ($url _arr[port])? $url _arr[port]: "80";
40. Connecting to a server
42. $fp = Fsockopen ($host, $port, $err _no, $err _str, 30);
44. if (! $fp) {return false;}
48. Construct the Request protocol
50. $request _str = "GET". $path. " http/1.1 ";
52. $request _str. = "Host:". $host. " ";
54. $request _str. = "Connection:close";
58. Send Request
60. Fwrite ($fp, $request _str);
62. $first _header = fgets ($fp, 1024);
64. Fclose ($FP);
68. Determine if a file exists
70. if (Trim ($first _header) = = "") {return false;}
72. if (!preg_match ("/200/", $first _header)) {
74. return false;
76. }
78. return true;
80. }
84. Test code
86. $str _url = http://www.ite5e.com/newsinfo.php?nid=1493;
88. $exits = remote_file_exists ($str _url);
90. Echo $exists? "Exists": "Not Exists";
92. ?>

http://www.bkjia.com/PHPjc/486160.html www.bkjia.com true http://www.bkjia.com/PHPjc/486160.html techarticle This article introduces PHP functions-to determine if a remote file exists an instance code? PHP/* Function: remote_file_exists function: Determine whether the remote file exists parameters: $url _file-remote file URL ...

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