Global Functions and Constants¶
CodeIgniter uses provides a few functions and variables that are globally defined, and are available to you at any point. These do not require loading any additional libraries or helpers.
Page Contents
Global Functions¶
Service Accessors¶
- cache([$key])¶
Parameters: - $key (string) – The cache name of the item to retrieve from cache (Optional)
Returns: Either the cache object, or the item retrieved from the cache
Return type: mixed
If no $key is provided, will return the Cache engine instance. If a $key is provided, will return the value of $key as stored in the cache currently, or false if no value is found.
Examples:
$foo = cache('foo'); $cache = cache();
- env($key[, $default=null])¶
Parameters: - $key (string) – The name of the environment variable to retrieve
- $default (mixed) – The default value to return if no value is found.
Returns: The environment variable, the default value, or null.
Return type: mixed
Used to retrieve values that have previously been set to the environment, or return a default value if it is not found. Will format boolean values to actual booleans instead of string representations.
Especially useful when used in conjunction with .env files for setting values that are specific to the environment itself, like database settings, API keys, etc.
- esc($data, $context='html'[, $encoding])¶
Parameters: - $data (string|array) – The information to be escaped.
- $context (string) – The escaping context. Default is ‘html’.
- $encoding (string) – The character encoding of the string.
Returns: The escaped data.
Return type: string
Escapes data for inclusion in web pages, to help prevent XSS attacks. This uses the Zend Escaper library to handle the actual filtering of the data.
If $data is a string, then it simply escapes and returns it. If $data is an array, then it loops over it, escaping each ‘value’ of the key/value pairs.
Valid context values: html, js, css, url, attr, raw, null
- helper($filename)¶
Parameters: - $filename (string) – The name of the helper file to load.
Loads a helper file.
For full details, see the Helper Functions page.
- lang(string $line[, array $args]): string
Parameters: - $line (string) – The line of text to retrieve
- $args (array) – An array of data to substitute for placeholders.
Retrieves a locale-specific file based on an alias string.
For more information, see the Localization page.
- session([$key])¶
Parameters: - $key (string) – The name of the session item to check for.
Returns: An instance of the Session object if no $key, the value found in the session for $key, or null.
Return type: mixed
Provides a convenient way to access the session class and to retrieve a stored value. For more information, see the Sessions page.
- timer([$name])¶
Parameters: - $name (string) – The name of the benchmark point.
Returns: The Timer instance
Return type: CodeIgniterDebugTimer
A convenience method that provides quick access to the Timer class. You can pass in the name of a benchmark point as the only parameter. This will start timing from this point, or stop timing if a timer with this name is already running.
Example:
// Get an instance $timer = timer(); // Set timer start and stop points timer('controller_loading'); // Will start the timer . . . timer('controller_loading'); // Will stop the running timer
- view($name[, $data[, $options]])¶
Parameters: - $name (string) – The name of the file to load
- $data (array) – An array of key/value pairs to make available within the view.
- $options (array) – An array of options that will be passed to the rendering class.
Returns: The output from the view.
Return type: string
Grabs the current RendererInterface-compatible class and tells it to render the specified view. Simply provides a convenience method that can be used in Controllers, libraries, and routed closures.
Currently, only one option is available for use within the $options array, saveData which specifies that data will persistent between multiple calls to view() within the same request. By default, the data for that view is forgotten after displaying that single view file.
The $option array is provided primarily to facilitate third-party integrations with libraries like Twig.
Example:
$data = ['user' => $user]; echo view('user_profile', $data);
For more details, see the Views page.
Miscellaneous Functions¶
- csrf_token()¶
Returns: The name of the current CSRF token. Return type: string Returns the name of the current CSRF token.
- csrf_hash()¶
Returns: The current value of the CSRF hash. Return type: string Returns the current CSRF hash value.
- csrf_field()¶
Returns: A string with the HTML for hidden input with all required CSRF information. Return type: string Returns a hidden input with the CSRF information already inserted:
<input type=”hidden” name=”{csrf_token}” value=”{csrf_hash}”>
- force_https($duration = 31536000[, $request = null[, $response = null]])¶
Parameters: - $duration (int) – The number of seconds browsers should convert links to this resource to HTTPS.
- $request (RequestInterface) – An instance of the current Request object.
- $response (ResponseInterface) – An instance of the current Response object.
Checks to see if the page is currently being accessed via HTTPS. If it is, then nothing happens. If it is not, then the user is redirected back to the current URI but through HTTPS. Will set the HTTP Strict Transport Security header, which instructs modern browsers to automatically modify any HTTP requests to HTTPS requests for the $duration.
- is_cli()¶
Returns: TRUE if the script is being executed from the command line or FALSE otherwise. Return type: bool
- log_message($level, $message[, array $context])¶
Parameters: - $level (string) – The level of severity
- $message (string) – The message that is to be logged.
- $context (array) – An associative array of tags and their values that should be replaced in $message
Returns: TRUE if was logged succesfully or FALSE if there was a problem logging it
Return type: bool
Logs a message using the Log Handlers defined in application/Config/Logger.php.
Level can be one of the following values: emergency, alert, critical, error, warning, notice, info, or debug.
Context can be used to substitute values in the message string. For full details, see the Logging Information page.
- redirect($uri[, ...$params])¶
Parameters: - $uri (string) – The URI to redirect the user to.
- $params (mixed) – one or more additional parameters that can be used with the RouteCollection::reverseRoute() method.
Convenience method that works with the current global $request and $router instances to redirect using named/reverse-routed routes to determine the URL to go to. If nothing is found, will treat as a traditional redirect and pass the string in, letting $response->redirect() determine the correct method and code.
If more control is needed, you must use $response->redirect() explicitly.
- redirect_with_input($uri[, ...$params])¶
Parameters: - $uri (string) – The URI to redirect the user to.
- $params (mixed) – one or more additional parameters that can be used with the RouteCollection::reverseRoute() method.
Identical to the redirect() method, except this flashes the request’s $_GET and $_POST values to the session. On the next page request, the form helper set_* methods will check for data within the old input first, then, if it’s not found, the current GET/POST will be checked.
Note
In order to retrieve the old, the session MUST be started prior to calling the function.
- remove_invisible_characters($str[, $url_encoded = TRUE])¶
Parameters: - $str (string) – Input string
- $url_encoded (bool) – Whether to remove URL-encoded characters as well
Returns: Sanitized string
Return type: string
This function prevents inserting NULL characters between ASCII characters, like Java\0script.
Example:
remove_invisible_characters('Java\\0script'); // Returns: 'Javascript'
- route_to($method[, ...$params])¶
Parameters: - $method (string) – The named route alias, or name of the controller/method to match.
- $params (mixed) – One or more parameters to be passed to be matched in the route.
Generates a relative URI for you based on either a named route alias, or a controller::method combination. Will take parameters into effect, if provided.
For full details, see the URI Routing page.
- service($name[, ...$params])¶
Parameters: - $name (string) – The name of the service to load
- $params (mixed) – One or more parameters to pass to the service method.
Returns: An instance of the service class specified.
Return type: mixed
Provides easy access to any of the Services defined in the system. This will always return a shared instance of the class, so no matter how many times this is called during a single request, only one class instance will be created.
Example:
$logger = service('logger'); $renderer = service('renderer', APPPATH.'views/');
- single_service($name[, ...$params])¶
Parameters: - $name (string) – The name of the service to load
- $params (mixed) – One or more parameters to pass to the service method.
Returns: An instance of the service class specified.
Return type: mixed
Identical to the service() function described above, except that all calls to this function will return a new instance of the class, where service returns the same instance every time.
- stringify_attributes($attributes[, $js])¶
Parameters: - $attributes (mixed) – string, array of key value pairs, or object
- $js (boolean) – TRUE if values do not need quotes (Javascript-style)
Returns: String containing the attribute key/value pairs, comma-separated
Return type: string
Helper function used to convert a string, array, or object of attributes to a string.
Global Constants¶
The following constants are always available anywhere within your application.
Core Constants¶
- constant ROOTPATH¶
The path to the main application directory. Just above public.
- constant APPPATH¶
The path to the application directory.
- constant BASEPATH¶
The path to the system directory.
- constant FCPATH¶
The path to the directory that holds the front controller.
- constant SELF¶
The path to the front controller, index.php.
- constant WRITEPATH¶
The path to the writable directory.