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user_guide_src/source/libraries/input.rst

Summary

Maintainability
Test Coverage
###########
Input Class
###########

The Input Class provides some helper methods for accessing input data
and pre-processing it.

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

.. contents::
  :local:

.. raw:: html

  <div class="custom-index container"></div>

********************
Accessing input data
********************

Using POST, GET, COOKIE, or SERVER Data
=======================================

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()``

Using the php://input stream
============================

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.

***************
Class Reference
***************

.. 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 = FALSE]])

        :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
        ::

            $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 retrieve 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 = FALSE]])

        :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 retrieve 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 = FALSE])

        :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 = FALSE])

        :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 = FALSE]])

        :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 = FALSE])

        :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 = FALSE]])

        :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 = 0[, $domain = ''[, $path = '/'[, $prefix = ''[, $secure = NULL[, $httponly = NULL]]]]]]])

        :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 the expiry
        time to a negative, or non-numeric value.

        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 *httponly* and *secure* flags, when omitted, will default to your
        ``$config['cookie_httponly']`` and ``$config['cookie_secure']`` settings.

        **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 = FALSE])

        :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() <https://secure.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:: 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