PHP - uitsetbeheerfunksies
PHP-uitsetbeheerfunksies
PHP bied 'n stel funksies wat beheer watter inhoud na die blaaier gestuur word en wanneer. Dit word na verwys as uitsetbeheer .
Uitset kan van enige van die volgende bronne kom:
echo,print,printf,print_r... en ander soortgelyke funksies en stellings- Kennisgewings, waarskuwings en foute van PHP
- Enige inhoud buite die
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PHP en die agterkant waarop dit loop, kan die uitvoer in 'n buffer hou voordat dit aan die gebruiker gestuur word.
Let wel: Die uitsetbeheerfunksies kan enige aantal uitsetbuffers skep. Uitsetbuffers vang uitset wat deur die program gegee word. Elke nuwe uitsetbuffer word bo-op 'n stapel uitsetbuffers geplaas, en enige uitset wat dit verskaf, sal deur die buffer daaronder opgevang word. Die uitsetbeheerfunksies hanteer slegs die boonste buffer, dus moet die boonste buffer verwyder word om die buffers daaronder te beheer.
Installasie
Die PHP-uitsetbeheerfunksies is deel van die PHP-kern. Geen installasie is nodig om hierdie funksies te gebruik nie.
Runtime-konfigurasie
Die gedrag van uitsetbeheerfunksies word beïnvloed deur instellings in php.ini:
| Name | Default | Description | Version |
|---|---|---|---|
| output_buffering | "0" | Enables output buffering for all PHP files by default | 4 |
| output_handler | NULL | Set the name of the default function which handles the output of all output buffers | 4 |
| implicit_flush | "0" | Enables implicit flush, which causes output to be sent directly to the browser on each output statement | 4 |
| url_rewriter.tags | "a=href,area=href, frame=src,form=,fieldset=" | Indicates which HTML tags and attributes can be modified by the URL rewriter (the output_add_rewrite_var() function.) | 4.3 |
| url_rewriter.hosts | The current value of $_SERVER['HTTP_HOST'] | URL rewriting is only done on the server's own URLs by default. To allow for rewriting URLs of other websites, set the hostnames of the other websites here. | 7.1 |
PHP-uitsetbeheerfunksies
| Method | Function |
|---|---|
| flush() | Attempts to send content from the system's output buffer to the browser |
| ob_clean() | Deletes all of the content from the topmost output buffer |
| ob_end_clean() | Deletes the topmost output buffer and all of its contents |
| ob_end_flush() | Deletes the topmost output buffer and outputs its contents |
| ob_flush() | Outputs the contents of the topmost output buffer and clears the buffer |
| ob_get_clean() | Returns all of the contents of the topmost output buffer and clears the buffer |
| ob_get_contents() | Returns the contents of the topmost output buffer |
| ob_get_flush() | Outputs and returns the contents of the topmost output buffer and then deletes the buffer |
| ob_get_length() | Returns the number of bytes of data that are in the topmost output buffer |
| ob_get_level() | Returns a number indicating how many output buffers are on the stack |
| ob_get_status() | Returns information about the output buffers |
| ob_gzhandler() | Used as a callback function for ob_start() to compress the contents of the buffer when sending it to the browser |
| ob_implicit_flush() | Turns implicit flushing on or off |
| ob_list_handlers() | Returns an array of callback function names that are being used by the topmost output buffer |
| ob_start() | Creates a new output buffer and adds it to the top of the stack |
| output_add_rewrite_var() | Used to append query string parameters to any URL in the output |
| output_reset_rewrite_vars() | Removes all variables added by output_add_rewrite_var() |