Superglobals
Superglobals are built-in variables that are always available in all scopes
Several predefined variables in PHP are "superglobals", which means they are available in all scopes throughout a script. There is no need to do global $variable; to access them within functions or methods.
These superglobal variables are:
$GLOBALS
$_SERVER
$_GET
$_POST
$_FILES
$_COOKIE
$_SESSION
$_REQUEST
$_ENV
-----------------------------------
-----------------------------------
$GLOBALS
References all variables available in global scope
An associative array containing references to all variables which are currently defined in the global scope of the script. The variable names are the keys of the array.
example
-----------------------------------
-----------------------------------
$_SERVER
Server and execution environment information
■ 8 useful server variables available in PHP: http://cdv.lt/Hs
-----------------------------------
$_SERVER['PHP_SELF']
The filename of the currently executing script, relative to the document root. For instance, $_SERVER['PHP_SELF'] in a script at the address
http://example.com/test.php/foo.bar would be /test.php/foo.bar. The __FILE__ constant contains the full path and filename of the current (i.e. included) file. If PHP is running as a command-line processor this variable contains the script name since PHP 4.3.0. Previously it was not available.
'argv'
Array of arguments passed to the script. When the script is run on the command line, this gives C-style access to the command line parameters. When called via the GET method, this will contain the query string.
'argc'
Contains the number of command line parameters passed to the script (if run on the command line).
-----------------------------------
$_SERVER['GATEWAY_INTERFACE']
What revision of the CGI specification the server is using; i.e. 'CGI/1.1'.
-----------------------------------
$_SERVER['SERVER_ADDR']
The IP address of the server under which the current script is executing.
-----------------------------------
$_SERVER['SERVER_NAME']
The name of the server host under which the current script is executing. If the script is running on a virtual host, this will be the value defined for that virtual host.
-----------------------------------
$_SERVER['SERVER_SOFTWARE']
Server identification string, given in the headers when responding to requests.
-----------------------------------
$_SERVER['SERVER_PROTOCOL']
Name and revision of the information protocol via which the page was requested; i.e. 'HTTP/1.0';
-----------------------------------
$_SERVER['REQUEST_METHOD']
Which request method was used to access the page; i.e. 'GET', 'HEAD', 'POST', 'PUT'.
Note:
PHP script is terminated after sending headers (it means after producing any output without output buffering) if the request method was HEAD.
-----------------------------------
$_SERVER['REQUEST_TIME']
The timestamp of the start of the request. Available since PHP 5.1.0.
-----------------------------------
$_SERVER['REQUEST_TIME_FLOAT']
The timestamp of the start of the request, with microsecond precision. Available since PHP 5.4.0.
-----------------------------------
$_SERVER['QUERY_STRING']
The query string, if any, via which the page was accessed.
-----------------------------------
$_SERVER['DOCUMENT_ROOT']
The document root directory under which the current script is executing, as defined in the server's configuration file.
-----------------------------------
$_SERVER['HTTP_ACCEPT']
Contents of the Accept: header from the current request, if there is one.
-----------------------------------
$_SERVER['HTTP_ACCEPT_CHARSET']
Contents of the Accept-Charset: header from the current request, if there is one. Example: 'iso-8859-1,,utf-8'.*
-----------------------------------
$_SERVER['HTTP_ACCEPT_ENCODING']
Contents of the Accept-Encoding: header from the current request, if there is one. Example: 'gzip'.
-----------------------------------
$_SERVER['HTTP_ACCEPT_LANGUAGE']
Contents of the Accept-Language: header from the current request, if there is one. Example: 'en'.
■ Detect Browser Language in PHP: http://cdv.lt/I5
-----------------------------------
$_SERVER['HTTP_CONNECTION']
Contents of the Connection: header from the current request, if there is one. Example: 'Keep-Alive'.
-----------------------------------
$_SERVER['HTTP_HOST']
Contents of the Host: header from the current request, if there is one.
-----------------------------------
$_SERVER['HTTP_REFERER']
The address of the page (if any) which referred the user agent to the current page. This is set by the user agent. Not all user agents will set this, and some provide the ability to modify HTTP_REFERER as a feature. In short, it cannot really be trusted.
-----------------------------------
$_SERVER['HTTP_USER_AGENT']
Contents of the User-Agent: header from the current request, if there is one. This is a string denoting the user agent being which is accessing the page. A typical example is: Mozilla/4.5 [en] (X11; U; Linux 2.2.9 i586). Among other things, you can use this value with get_browser() to tailor your page's output to the capabilities of the user agent.
-----------------------------------
$_SERVER['HTTPS']
Set to a non-empty value if the script was queried through the HTTPS protocol.
Note: Note that when using ISAPI with IIS, the value will be off if the request was not made through the HTTPS protocol.
-----------------------------------
$_SERVER['REMOTE_ADDR']
The IP address from which the user is viewing the current page.
-----------------------------------
$_SERVER['REMOTE_HOST']
The Host name from which the user is viewing the current page. The reverse dns lookup is based off the REMOTE_ADDR of the user.
Note: Your web server must be configured to create this variable. For example in Apache you'll need HostnameLookups On inside httpd.conf for it to exist. See also gethostbyaddr().
-----------------------------------
$_SERVER['REMOTE_PORT']
The port being used on the user's machine to communicate with the web server.
-----------------------------------
$_SERVER['REMOTE_USER']
The authenticated user.
-----------------------------------
$_SERVER['REDIRECT_REMOTE_USER']
The authenticated user if the request is internally redirected.
-----------------------------------
$_SERVER['SCRIPT_FILENAME']
The absolute pathname of the currently executing script.
Note:
If a script is executed with the CLI, as a relative path, such as file.php or ../file.php, $_SERVER['SCRIPT_FILENAME'] will contain the relative path specified by the user.
-----------------------------------
$_SERVER['SERVER_ADMIN']
The value given to the SERVER_ADMIN (for Apache) directive in the web server configuration file. If the script is running on a virtual host, this will be the value defined for that virtual host.
-----------------------------------
$_SERVER['SERVER_PORT']
The port on the server machine being used by the web server for communication. For default setups, this will be '80'; using SSL, for instance, will change this to whatever your defined secure HTTP port is.
-----------------------------------
$_SERVER['SERVER_SIGNATURE']
String containing the server version and virtual host name which are added to server-generated pages, if enabled.
-----------------------------------
$_SERVER['PATH_TRANSLATED']
Filesystem- (not document root-) based path to the current script, after the server has done any virtual-to-real mapping.
Note: As of PHP 4.3.2, PATH_TRANSLATED is no longer set implicitly under the Apache 2 SAPI in contrast to the situation in Apache 1, where it's set to the same value as the SCRIPT_FILENAME server variable when it's not populated by Apache. This change was made to comply with the CGI specification that PATH_TRANSLATED should only exist if PATH_INFO is defined. Apache 2 users may use AcceptPathInfo = On inside httpd.conf to define PATH_INFO.
-----------------------------------
$_SERVER['SCRIPT_NAME']
Contains the current script's path. This is useful for pages which need to point to themselves. The __FILE__ constant contains the full path and filename of the current (i.e. included) file.
-----------------------------------
$_SERVER['REQUEST_URI']
The URI which was given in order to access this page; for instance, '/index.html'.
-----------------------------------
$_SERVER['PHP_AUTH_DIGEST']
When doing Digest HTTP authentication this variable is set to the 'Authorization' header sent by the client (which you should then use to make the appropriate validation).
-----------------------------------
$_SERVER['PHP_AUTH_USER']
When doing HTTP authentication this variable is set to the username provided by the user.
-----------------------------------
$_SERVER['PHP_AUTH_PW']
When doing HTTP authentication this variable is set to the password provided by the user.
-----------------------------------
$_SERVER['AUTH_TYPE']
When doing HTTP authenticated this variable is set to the authentication type.
-----------------------------------
$_SERVER['PATH_INFO']
Contains any client-provided pathname information trailing the actual script filename but preceding the query string, if available. For instance, if the current script was accessed via the URL http://www.example.com/php/path_info.php/some/stuff?foo=bar, then $_SERVER['PATH_INFO'] would contain /some/stuff.
-----------------------------------
$_SERVER['ORIG_PATH_INFO']
Original version of 'PATH_INFO' before processed by PHP.
-----------------------------------
-----------------------------------
$_GET
HTTP GET variables
-----------------------------------
-----------------------------------
$_POST
HTTP POST variables
-----------------------------------
-----------------------------------
$_FILES
HTTP File Upload variables
-----------------------------------
-----------------------------------
$_REQUEST
HTTP Request variables
An associative array that by default contains the contents of $_GET, $_POST and $_COOKIE.
-----------------------------------
-----------------------------------
$_SESSION
Session variables
An associative array containing session variables available to the current script. See the Session functions documentation for more information on how this is used.
Session functions:
http://php.net/manual/en/ref.session.php
-----------------------------------
-----------------------------------
$_ENV
Environment variables
An associative array of variables passed to the current script via the environment method.
These variables are imported into PHP's global namespace from the environment under which the PHP parser is running. Many are provided by the shell under which PHP is running and different systems are likely running different kinds of shells, a definitive list is impossible. Please see your shell's documentation for a list of defined environment variables.
-----------------------------------
-----------------------------------
$_COOKIE
HTTP Cookies
An associative array of variables passed to the current script via HTTP Cookies.
-----------------------------------
-----------------------------------
$php_errormsg
*The previous error message
$php_errormsg is a variable containing the text of the last error message generated by PHP. This variable will only be available within the scope in which the error occurred, and only if the track_errors configuration option is turned on (it defaults to off).*
Note: This variable is only available when track_errors is enabled in php.ini.
Warning: If a user defined error handler ( set_error_handler()) is set $php_errormsg is only set if the error handler returns FALSE.
-----------------------------------
-----------------------------------
$HTTP_RAW_POST_DATA
Raw POST data
$HTTP_RAW_POST_DATA contains the raw POST data.
See always_populate_raw_post_data
http://php.net/manual/en/ini.core.php#ini.always-populate-raw-post-data
-----------------------------------
-----------------------------------
$http_response_header
HTTP response headers
The $http_response_header array is similar to the
get_headers() function. When using the HTTP wrapper,
$http_response_header will be populated with the HTTP response headers.
$http_response_header will be created in the
local scope.
http://php.net/manual/en/wrappers.http.php
http://php.net/manual/en/language.variables.scope.php
-----------------------------------
-----------------------------------
$argc
The number of arguments passed to script
Contains the number of arguments passed to the current script when running from the command line.
Note: The script's filename is always passed as an argument to the script, therefore the minimum value of $argc is 1.
Note: This variable is not available when register_argc_argv is disabled.
-----------------------------------
-----------------------------------
$argv
Array of arguments passed to script
Contains an array of all the arguments passed to the script when running from the command line.
Note: The first argument $argv[0] is always the name that was used to run the script.
Note: This variable is not available when register_argc_argv is disabled.
-----------------------------------
Created By
Metadata
Favourited By
and 25 more ...
Comments
G 09:34 31 Oct 14
Thank you!
archerdgreat, 15:11 4 Dec 15
thanks so much!
lastick, 23:16 22 Sep 20
Great concept
Thank You!
pierre78, 13:25 24 Sep 20
Thanks !
Add a Comment
Related Cheat Sheets