Introduction to several php post Data Acquisition Techniques

For an experienced

(1) PHP obtains POST data when the form POST method is submitted

$ _ POST and php: // input can get the value. $ HTTP_RAW_POST_DATA is empty.
$ _ POST organizes submitted data in an associated array and performs encoding, such as urldecode or even encoding conversion.
Php: // input: Raw POST data that has not been processed can be obtained by reading files from the input stream.

(2) fsockopen submits POST data and PHP obtains POST data

1. $ Sock = fsockopen ("localhost", 80,
   $ Errno, $ errstr, 30 );
2. If (! $ Sock) die ("$ errstr ($ errno) n ");
3. $ Data = "txt =". urlencode ("medium ").
   "& Bar =". urlencode ("Value for Bar ");
4. Fwrite ($ sock, "POST/posttest/response
   . Php HTTP/1.0rn ");
5. Fwrite ($ sock, "Host: localhostrn ");
6. Fwrite ($ sock, "Content-type: applicat
   Ion/x-www-form-urlencodedrn ");
7. Fwrite ($ sock, "Content-length :".
   Strlen ($ data). "rn ");
8. Fwrite ($ sock, "Accept: */* rn ");
9. Fwrite ($ sock, "rn ");
10. Fwrite ($ sock, "$ datarn ");
11. Fwrite ($ sock, "rn ");
12. $ Headers = "";
13. While ($ str = trim (fgets ($ sock,
    4096 )))
14. $ Headers. = "$ strn ";
15. Echo "n ";
16. $ Body = "";
17. While (! Feof ($ sock ))
18. $ Body. = fgets ($ sock, 4096 );
19. Fclose ($ sock );
20. Echo $ body;

PHP obtains POST data. Conclusion:

1. You can use php: // input to conveniently retrieve the original POST data.

2. $ HTTP_RAW_POST_DATA is valid only when the POST Content-Type is not recognized by PHP.

For example, the POST data submitted through the page form cannot be extracted through $ HTTP_RAW_POST_DATA. The encoding type attribute (enctype attribute) is application/x-www-form-urlencoded and multipart/form-data.

Note: even if the enctype attribute is explicitly changed to an unrecognized PHP type on the page, it still does not work. Because the form submission encoding attribute is a form limitation, unrecognized types are considered to be submitted in the default encoding mode (application/x-www-form-urlencoded)

3. $ _ POST: PHP can obtain POST data only when data is submitted by application/x-www-form-urlencoded type.