Phpob_start (ob_gzhandler) for web page compression

First, let's take a look at the ob_start usage and use the PHPob_start () function to open the browser cache. This ensures that the cache content is completed when you call flush (), ob_end_flush () (or the program execution is completed.

First, let's take a look at the ob_start usage. use the PHP ob_start () function to open the browser cache. This ensures that the cache content is displayed after you call flush (), ob_end_flush () (or program execution is completed) the code is as follows:

2. Ob_start (); // open the buffer
3. Phpinfo (); // use the phpinfo function
4. $ Info = ob_get_contents (); // Obtain the buffer content and assign it to $ info
5. Using file1_fopen('info.txt ', 'w'); // open the info.txt file.
6. Fwrite ($ file, $ info); // write the information to info.txt
7. Fclose ($ file); // Close the info.txt file
8. ?>

PHP ob_start () functions have a great feature. you can also use the ob_start parameter to automatically run commands after the cache is written, such as ob_start ("ob_gzhandler "); the most common practice is to use ob_get_contents () to get the code of the content in the cache as an example of compressing the web page. We use the ob_gzip function, use ob_start to compress the output content and put it in the "buffer zone". the code is as follows:

1. // Enable compression
2. If (function_exists ('OB _ gzip '))
3. {
4. Ob_start ('OB _ gzip ');
5. }
6. // Prepare some content to be compressed
7. For ($ I = 0; I I <100; $ I ++)
8. {
9. Echo ('Here is the test content.
   ');
10. }
11. // Output compressed results
12. Ob_end_flush ();
13. // This is the ob_gzip compression function.
14. Function ob_gzip ($ content)
15. {
16. If (! Headers_sent () & extension_loaded ("zlib") & strstr ($ _ SERVER ["HTTP_ACCEPT_ENCODING"], "gzip ")){
17. $ Content = gzencode ($ content, 9 );
18. Header ("Content-Encoding: gzip ");
19. Header ("Vary: Accept-Encoding ");
20. Header ("Content-Length:". strlen ($ content ));
21. }
22. Return ($ content );
23. }