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Input Class

The Input Class serves two purposes:

  1. It pre-processes global input data for security.
  2. It provides some helper methods for fetching input data and pre-processing it.

Note

This class is initialized automatically by the system so there is no need to do it manually.

The security filtering method is called automatically when a new :doc:`controller <../general/controllers>` is invoked. It does the following:

  • If $config['allow_get_array'] is FALSE (default is TRUE), destroys the global GET array.
  • Destroys all global variables in the event register_globals is turned on.
  • Filters the GET/POST/COOKIE array keys, permitting only alpha-numeric (and a few other) characters.
  • Provides XSS (Cross-site Scripting Hacks) filtering. This can be enabled globally, or upon request.
  • Standardizes newline characters to PHP_EOL (\n in UNIX-based OSes, \r\n under Windows). This is configurable.

The Input class has the ability to filter input automatically to prevent cross-site scripting attacks. If you want the filter to run automatically every time it encounters POST or COOKIE data you can enable it by opening your application/config/config.php file and setting this:

$config['global_xss_filtering'] = TRUE;

Please refer to the :doc:`Security class <security>` documentation for information on using XSS Filtering in your application.

Important

The 'global_xss_filtering' setting is DEPRECATED and kept solely for backwards-compatibility purposes. XSS escaping should be performed on output, not input!

CodeIgniter comes with helper methods that let you fetch POST, GET, COOKIE or SERVER items. The main advantage of using the provided methods rather than fetching an item directly ($_POST['something']) is that the methods will check to see if the item is set and return NULL if not. This lets you conveniently use data without having to test whether an item exists first. In other words, normally you might do something like this:

$something = isset($_POST['something']) ? $_POST['something'] : NULL;

With CodeIgniter's built in methods you can simply do this:

$something = $this->input->post('something');

The main methods are:

  • $this->input->post()
  • $this->input->get()
  • $this->input->cookie()
  • $this->input->server()

If you want to utilize the PUT, DELETE, PATCH or other exotic request methods, they can only be accessed via a special input stream, that can only be read once. This isn't as easy as just reading from e.g. the $_POST array, because it will always exist and you can try and access multiple variables without caring that you might only have one shot at all of the POST data.

CodeIgniter will take care of that for you, and you can read the data from the php://input stream at any time, just by using the $raw_input_stream property:

$this->input->raw_input_stream;

Additionally if the input stream is form-encoded like $_POST you can access its values by calling the input_stream() method:

$this->input->input_stream('key');

Similar to other methods such as get() and post(), if the requested data is not found, it will return NULL and you can also decide whether to run the data through xss_clean() by passing a boolean value as the second parameter:

$this->input->input_stream('key', TRUE); // XSS Clean
$this->input->input_stream('key', FALSE); // No XSS filter

Note

You can utilize method() in order to know if you're reading PUT, DELETE or PATCH data.

.. php:class:: CI_Input

        .. attribute:: $raw_input_stream

                Read only property that will return php://input data as is.

                The property can be read multiple times.

        .. php:method:: post([$index = NULL[, $xss_clean = NULL]])

                :param  mixed   $index: POST parameter name
                :param  bool    $xss_clean: Whether to apply XSS filtering
                :returns:       $_POST if no parameters supplied, otherwise the POST value if found or NULL if not
                :rtype: mixed

                The first parameter will contain the name of the POST item you are
                looking for::

                        $this->input->post('some_data');

                The method returns NULL if the item you are attempting to retrieve
                does not exist.

                The second optional parameter lets you run the data through the XSS
                filter. It's enabled by setting the second parameter to boolean TRUE
                or by setting your ``$config['global_xss_filtering']`` to TRUE.
                ::

                        $this->input->post('some_data', TRUE);

                To return an array of all POST items call without any parameters.

                To return all POST items and pass them through the XSS filter set the
                first parameter NULL while setting the second parameter to boolean TRUE.
                ::

                        $this->input->post(NULL, TRUE); // returns all POST items with XSS filter
                        $this->input->post(NULL, FALSE); // returns all POST items without XSS filter

                To return an array of multiple POST parameters, pass all the required keys
                as an array.
                ::

                        $this->input->post(array('field1', 'field2'));

                Same rule applied here, to retrive the parameters with XSS filtering enabled, set the
                second parameter to boolean TRUE.
                ::

                        $this->input->post(array('field1', 'field2'), TRUE);

        .. php:method:: get([$index = NULL[, $xss_clean = NULL]])

                :param  mixed   $index: GET parameter name
                :param  bool    $xss_clean: Whether to apply XSS filtering
                :returns:       $_GET if no parameters supplied, otherwise the GET value if found or NULL if not
                :rtype: mixed

                This method is identical to ``post()``, only it fetches GET data.
                ::

                        $this->input->get('some_data', TRUE);

                To return an array of all GET items call without any parameters.

                To return all GET items and pass them through the XSS filter set the
                first parameter NULL while setting the second parameter to boolean TRUE.
                ::

                        $this->input->get(NULL, TRUE); // returns all GET items with XSS filter
                        $this->input->get(NULL, FALSE); // returns all GET items without XSS filtering

                To return an array of multiple GET parameters, pass all the required keys
                as an array.
                ::

                        $this->input->get(array('field1', 'field2'));

                Same rule applied here, to retrive the parameters with XSS filtering enabled, set the
                second parameter to boolean TRUE.
                ::

                        $this->input->get(array('field1', 'field2'), TRUE);

        .. php:method:: post_get($index[, $xss_clean = NULL])

                :param  string  $index: POST/GET parameter name
                :param  bool    $xss_clean: Whether to apply XSS filtering
                :returns:       POST/GET value if found, NULL if not
                :rtype: mixed

                This method works pretty much the same way as ``post()`` and ``get()``,
                only combined. It will search through both POST and GET streams for data,
                looking in POST first, and then in GET::

                        $this->input->post_get('some_data', TRUE);

        .. php:method:: get_post($index[, $xss_clean = NULL])

                :param  string  $index: GET/POST parameter name
                :param  bool    $xss_clean: Whether to apply XSS filtering
                :returns:       GET/POST value if found, NULL if not
                :rtype: mixed

                This method works the same way as ``post_get()`` only it looks for GET
                data first.

                        $this->input->get_post('some_data', TRUE);

                .. note:: This method used to act EXACTLY like ``post_get()``, but it's
                        behavior has changed in CodeIgniter 3.0.

        .. php:method:: cookie([$index = NULL[, $xss_clean = NULL]])

                :param  mixed   $index: COOKIE name
                :param  bool    $xss_clean: Whether to apply XSS filtering
                :returns:       $_COOKIE if no parameters supplied, otherwise the COOKIE value if found or NULL if not
                :rtype: mixed

                This method is identical to ``post()`` and ``get()``, only it fetches cookie
                data::

                        $this->input->cookie('some_cookie');
                        $this->input->cookie('some_cookie, TRUE); // with XSS filter

                To return an array of multiple cookie values, pass all the required keys
                as an array.
                ::

                        $this->input->cookie(array('some_cookie', 'some_cookie2'));

                .. note:: Unlike the :doc:`Cookie Helper <../helpers/cookie_helper>`
                        function :php:func:`get_cookie()`, this method does NOT prepend
                        your configured ``$config['cookie_prefix']`` value.

        .. php:method:: server($index[, $xss_clean = NULL])

                :param  mixed   $index: Value name
                :param  bool    $xss_clean: Whether to apply XSS filtering
                :returns:       $_SERVER item value if found, NULL if not
                :rtype: mixed

                This method is identical to the ``post()``, ``get()`` and ``cookie()``
                methods, only it fetches server data (``$_SERVER``)::

                        $this->input->server('some_data');

                To return an array of multiple ``$_SERVER`` values, pass all the required keys
                as an array.
                ::

                        $this->input->server(array('SERVER_PROTOCOL', 'REQUEST_URI'));

        .. php:method:: input_stream([$index = NULL[, $xss_clean = NULL]])

                :param  mixed   $index: Key name
                :param  bool    $xss_clean: Whether to apply XSS filtering
                :returns:       Input stream array if no parameters supplied, otherwise the specified value if found or NULL if not
                :rtype: mixed

                This method is identical to ``get()``, ``post()`` and ``cookie()``,
                only it fetches the *php://input* stream data.

        .. php:method:: set_cookie($name = ''[, $value = ''[, $expire = ''[, $domain = ''[, $path = '/'[, $prefix = ''[, $secure = FALSE[, $httponly = FALSE]]]]]]])

                :param  mixed   $name: Cookie name or an array of parameters
                :param  string  $value: Cookie value
                :param  int     $expire: Cookie expiration time in seconds
                :param  string  $domain: Cookie domain
                :param  string  $path: Cookie path
                :param  string  $prefix: Cookie name prefix
                :param  bool    $secure: Whether to only transfer the cookie through HTTPS
                :param  bool    $httponly: Whether to only make the cookie accessible for HTTP requests (no JavaScript)
                :rtype: void


                Sets a cookie containing the values you specify. There are two ways to
                pass information to this method so that a cookie can be set: Array
                Method, and Discrete Parameters:

                **Array Method**

                Using this method, an associative array is passed to the first
                parameter::

                        $cookie = array(
                                'name'   => 'The Cookie Name',
                                'value'  => 'The Value',
                                'expire' => '86500',
                                'domain' => '.some-domain.com',
                                'path'   => '/',
                                'prefix' => 'myprefix_',
                                'secure' => TRUE
                        );

                        $this->input->set_cookie($cookie);

                **Notes**

                Only the name and value are required. To delete a cookie set it with the
                expiration blank.

                The expiration is set in **seconds**, which will be added to the current
                time. Do not include the time, but rather only the number of seconds
                from *now* that you wish the cookie to be valid. If the expiration is
                set to zero the cookie will only last as long as the browser is open.

                For site-wide cookies regardless of how your site is requested, add your
                URL to the **domain** starting with a period, like this:
                .your-domain.com

                The path is usually not needed since the method sets a root path.

                The prefix is only needed if you need to avoid name collisions with
                other identically named cookies for your server.

                The secure boolean is only needed if you want to make it a secure cookie
                by setting it to TRUE.

                **Discrete Parameters**

                If you prefer, you can set the cookie by passing data using individual
                parameters::

                        $this->input->set_cookie($name, $value, $expire, $domain, $path, $prefix, $secure);

        .. php:method:: ip_address()

                :returns:       Visitor's IP address or '0.0.0.0' if not valid
                :rtype: string

                Returns the IP address for the current user. If the IP address is not
                valid, the method will return '0.0.0.0'::

                        echo $this->input->ip_address();

                .. important:: This method takes into account the ``$config['proxy_ips']``
                        setting and will return the reported HTTP_X_FORWARDED_FOR,
                        HTTP_CLIENT_IP, HTTP_X_CLIENT_IP or HTTP_X_CLUSTER_CLIENT_IP
                        address for the allowed IP addresses.

        .. php:method:: valid_ip($ip[, $which = ''])

                :param  string  $ip: IP address
                :param  string  $which: IP protocol ('ipv4' or 'ipv6')
                :returns:       TRUE if the address is valid, FALSE if not
                :rtype: bool

                Takes an IP address as input and returns TRUE or FALSE (boolean) depending
                on whether it is valid or not.

                .. note:: The $this->input->ip_address() method above automatically
                        validates the IP address.

                ::

                        if ( ! $this->input->valid_ip($ip))
                        {
                                echo 'Not Valid';
                        }
                        else
                        {
                                echo 'Valid';
                        }

                Accepts an optional second string parameter of 'ipv4' or 'ipv6' to specify
                an IP format. The default checks for both formats.

        .. php:method:: user_agent([$xss_clean = NULL])

                :returns:       User agent string or NULL if not set
                :param  bool    $xss_clean: Whether to apply XSS filtering
                :rtype: mixed

                Returns the user agent string (web browser) being used by the current user,
                or NULL if it's not available.
                ::

                        echo $this->input->user_agent();

                See the :doc:`User Agent Class <user_agent>` for methods which extract
                information from the user agent string.

        .. php:method:: request_headers([$xss_clean = FALSE])

                :param  bool    $xss_clean: Whether to apply XSS filtering
                :returns:       An array of HTTP request headers
                :rtype: array

                Returns an array of HTTP request headers.
                Useful if running in a non-Apache environment where
                `apache_request_headers() <http://php.net/apache_request_headers>`_
                will not be supported.
                ::

                        $headers = $this->input->request_headers();

        .. php:method:: get_request_header($index[, $xss_clean = FALSE])

                :param  string  $index: HTTP request header name
                :param  bool    $xss_clean: Whether to apply XSS filtering
                :returns:       An HTTP request header or NULL if not found
                :rtype: string

                Returns a single member of the request headers array or NULL
                if the searched header is not found.
                ::

                        $this->input->get_request_header('some-header', TRUE);

        .. php:method:: is_ajax_request()

                :returns:       TRUE if it is an Ajax request, FALSE if not
                :rtype: bool

                Checks to see if the HTTP_X_REQUESTED_WITH server header has been
                set, and returns boolean TRUE if it is or FALSE if not.

        .. php:method:: is_cli_request()

                :returns:       TRUE if it is a CLI request, FALSE if not
                :rtype: bool

                Checks to see if the application was run from the command-line
                interface.

                .. note:: This method checks both the PHP SAPI name currently in use
                        and if the ``STDIN`` constant is defined, which is usually a
                        failsafe way to see if PHP is being run via the command line.

                ::

                        $this->input->is_cli_request()

                .. note:: This method is DEPRECATED and is now just an alias for the
                        :func:`is_cli()` function.

        .. php:method:: method([$upper = FALSE])

                :param  bool    $upper: Whether to return the request method name in upper or lower case
                :returns:       HTTP request method
                :rtype: string

                Returns the ``$_SERVER['REQUEST_METHOD']``, with the option to set it
                in uppercase or lowercase.
                ::

                        echo $this->input->method(TRUE); // Outputs: POST
                        echo $this->input->method(FALSE); // Outputs: post
                        echo $this->input->method(); // Outputs: post