Class AppModel
Application model for Cake.
This is a placeholder class. Create the same file in app/app_model.php Add your application-wide methods to the class, your models will inherit them.
- Object
-
Overloadable
-
Model
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AppModel
Direct Subclasses
Copyright: Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
License: License (http://www.opensource.org/licenses/mit-license.php)
Location: model/app_model.php
Inherited Properties
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Behaviors,__affectedRows,__associationKeys,__associations,__backAssociation,__insertID,__numRows,__safeUpdateMode,_findMethods,_schema,actsAs,alias,belongsTo,cacheQueries,cacheSources,data,displayField,findQueryType,hasAndBelongsToMany,hasMany,hasOne,id,logTransactions,name,order,primaryKey,recursive,table,tablePrefix,tableToModel,useDbConfig,useTable,validate,validationErrors,virtualFields,whitelist
Methods inherited from Model
__collectForeignKeys() public ¶
__collectForeignKeys( $type = 'belongsTo' )
Collects foreign keys from associations.
Returns
__construct() public ¶
__construct( mixed $id = false , string $table = null , string $ds = null )
Constructor. Binds the model's database table to the object.
If $id is an array it can be used to pass several options into the model.
- id - The id to start the model on.
- table - The table to use for this model.
- ds - The connection name this model is connected to.
- name - The name of the model eg. Post.
- alias - The alias of the model, this is used for registering the instance in the
ClassRegistry. eg.ParentThread
Overriding Model's __construct method.
When overriding Model::__construct() be careful to include and pass in all 3 of the
arguments to parent::__construct($id, $table, $ds);
Dynamically creating models
You can dynamically create model instances using the $id array syntax.
{{{ $Post = new Model(array('table' => 'posts', 'name' => 'Post', 'ds' => 'connection2')); }}}
Would create a model attached to the posts table on connection2. Dynamic model creation is useful when you want a model object that contains no associations or attached behaviors.
Parameters
- mixed $id optional false
- Set this ID for this model on startup, can also be an array of options, see above.
- string $table optional null
- Name of database table to use.
- string $ds optional null
- DataSource connection name.
Overrides
__constructLinkedModel() public deprecated ¶
__constructLinkedModel( string $assoc , string $className = null )
Private helper method to create associated models of a given class.
Deprecated
$this->$className use $this->$assoc instead. $assoc is the 'key' in the associations array; examples: var $hasMany = array('Assoc' => array('className' => 'ModelName')); usage: $this->Assoc->modelMethods();
var $hasMany = array('ModelName');
usage: $this->ModelName->modelMethods();
Parameters
- string $assoc
- Association name
- string $className optional null
- Class name
__filterResults() public ¶
__filterResults( array $results , boolean $primary = true )
Passes query results through model and behavior afterFilter() methods.
Parameters
- array $results
- to filter
- boolean $primary optional true
- If this is the primary model results (results from model where the find operation was performed)
Returns
Set of filtered results
__generateAssociation() public ¶
__generateAssociation( string $type )
Build an array-based association from string.
Parameters
- string $type
- 'belongsTo', 'hasOne', 'hasMany', 'hasAndBelongsToMany'
__save() public ¶
__save( $data , $options )
Private helper method used by saveAll.
Returns
Success
See
__saveMulti() public ¶
__saveMulti( array $joined , mixed $id , $db )
Saves model hasAndBelongsToMany data to the database.
Parameters
- array $joined
- Data to save
- mixed $id
- ID of record in this model
- $db
__sleep() public ¶
__sleep( )
Called when serializing a model.
Returns
Set of object variable names this model has
__validateWithModels() public ¶
__validateWithModels( array $options )
Runs validation for hasAndBelongsToMany associations that have 'with' keys set. And data in the set() data set.
Parameters
- array $options
- Array of options to use on Valdation of with models
Returns
Failure of validation on with models.
See
_clearCache() public ¶
_clearCache( string $type = null )
Private method. Clears cache for this model.
Parameters
- string $type optional null
If null this deletes cached views if Cache.check is true Will be used to allow deleting query cache also
Returns
true on delete
_deleteDependent() public ¶
_deleteDependent( string $id , boolean $cascade )
Cascades model deletes through associated hasMany and hasOne child records.
Parameters
- string $id
- ID of record that was deleted
- boolean $cascade
- Set to true to delete records that depend on this record
_deleteLinks() public ¶
_deleteLinks( string $id )
Cascades model deletes through HABTM join keys.
Parameters
- string $id
- ID of record that was deleted
_findCount() public ¶
_findCount( string $state , array $query , array $results = array() )
Handles the before/after filter logic for find('count') operations. Only called by Model::find().
Parameters
- string $state
- Either "before" or "after"
- array $query
- array $results optional array()
- $data
Returns
The number of records found, or false
See
_findFirst() public ¶
_findFirst( string $state , array $query , array $results = array() )
Handles the before/after filter logic for find('first') operations. Only called by Model::find().
Parameters
- string $state
- Either "before" or "after"
- array $query
- array $results optional array()
- $data
Returns
See
_findList() public ¶
_findList( string $state , array $query , array $results = array() )
Handles the before/after filter logic for find('list') operations. Only called by Model::find().
Parameters
- string $state
- Either "before" or "after"
- array $query
- array $results optional array()
- $data
Returns
Key/value pairs of primary keys/display field values of all records found
See
_findNeighbors() public ¶
_findNeighbors( string $state , mixed $query , array $results = array() )
Detects the previous field's value, then uses logic to find the 'wrapping' rows and return them.
Parameters
- string $state
- Either "before" or "after"
- mixed $query
- array $results optional array()
Returns
_findThreaded() public ¶
_findThreaded( mixed $state , mixed $query , array $results = array() )
In the event of ambiguous results returned (multiple top level results, with different parent_ids) top level results with different parent_ids to the first result will be dropped
Parameters
- mixed $state
- mixed $query
- array $results optional array()
Returns
Threaded results
_prepareUpdateFields() public ¶
_prepareUpdateFields( array $data )
Helper method for Model::updateCounterCache(). Checks the fields to be updated for
Parameters
- array $data
- The fields of the record that will be updated
Returns
Returns updated foreign key values, along with an 'old' key containing the old values, or empty if no foreign keys are updated.
afterFind() public ¶
afterFind( mixed $results , boolean $primary = false )
Called after each find operation. Can be used to modify any results returned by find(). Return value should be the (modified) results.
Parameters
- mixed $results
- The results of the find operation
- boolean $primary optional false
- Whether this model is being queried directly (vs. being queried as an association)
Returns
Result of the find operation
Link
afterSave() public ¶
afterSave( boolean $created )
Called after each successful save operation.
Parameters
- boolean $created
- True if this save created a new record
Link
beforeDelete() public ¶
beforeDelete( boolean $cascade = true )
Called before every deletion operation.
Parameters
- boolean $cascade optional true
- If true records that depend on this record will also be deleted
Returns
True if the operation should continue, false if it should abort
Link
beforeFind() public ¶
beforeFind( array $queryData )
Called before each find operation. Return false if you want to halt the find call, otherwise return the (modified) query data.
Parameters
- array $queryData
- Data used to execute this query, i.e. conditions, order, etc.
Returns
true if the operation should continue, false if it should abort; or, modified $queryData to continue with new $queryData
Link
beforeSave() public ¶
beforeSave( $options = array() )
Called before each save operation, after validation. Return a non-true result to halt the save.
Returns
True if the operation should continue, false if it should abort
Link
beforeValidate() public ¶
beforeValidate( $options = array() )
Called during validation operations, before validation. Please note that custom validation rules can be defined in $validate.
Parameters
- $options optional array()
- Options passed from model::save(), see $options of model::save().
Returns
True if validate operation should continue, false to abort
Link
bindModel() public ¶
bindModel( array $params , boolean $reset = true )
Bind model associations on the fly.
If $reset is false, association will not be reset
to the originals defined in the model
Example: Add a new hasOne binding to the Profile model not defined in the model source code:
$this->User->bindModel( array('hasOne' => array('Profile')) );
Bindings that are not made permanent will be reset by the next Model::find() call on this model.
Parameters
- array $params
- Set of bindings (indexed by binding type)
- boolean $reset optional true
- Set to false to make the binding permanent
Returns
Success
Link
call__() public ¶
call__( string $method , array $params )
Handles custom method calls, like findBy
Parameters
- string $method
- Name of method to call.
- array $params
- Parameters for the method.
Returns
Whatever is returned by called method
create() public ¶
create( mixed $data = array() , boolean $filterKey = false )
Initializes the model for writing a new record, loading the default values for those fields that are not defined in $data, and clearing previous validation errors. Especially helpful for saving data in loops.
Parameters
- mixed $data optional array()
Optional data array to assign to the model after it is created. If null or false, schema data defaults are not merged.
- boolean $filterKey optional false
- If true, overwrites any primary key input with an empty value
Returns
The current Model::data; after merging $data and/or defaults from database
Link
deconstruct() public ¶
deconstruct( string $field , mixed $data )
Deconstructs a complex data type (array or object) into a single field value.
Parameters
- string $field
- The name of the field to be deconstructed
- mixed $data
- An array or object to be deconstructed into a field
Returns
The resulting data that should be assigned to a field
delete() public ¶
delete( mixed $id = null , boolean $cascade = true )
Removes record for given ID. If no ID is given, the current ID is used. Returns true on success.
Parameters
- mixed $id optional null
- ID of record to delete
- boolean $cascade optional true
- Set to true to delete records that depend on this record
Returns
True on success
Link
deleteAll() public ¶
deleteAll( mixed $conditions , boolean $cascade = true , boolean $callbacks = false )
Deletes multiple model records based on a set of conditions.
Parameters
- mixed $conditions
- Conditions to match
- boolean $cascade optional true
- Set to true to delete records that depend on this record
- boolean $callbacks optional false
- Run callbacks
Returns
True on success, false on failure
Link
escapeField() public ¶
escapeField( string $field = null , string $alias = null )
Escapes the field name and prepends the model name. Escaping is done according to the current database driver's rules.
Parameters
- string $field optional null
- Field to escape (e.g: id)
- string $alias optional null
- Alias for the model (e.g: Post)
Returns
The name of the escaped field for this Model (i.e. id becomes
Post.id).exists() public ¶
exists( )
Returns true if a record with the currently set ID exists.
Internally calls Model::getID() to obtain the current record ID to verify, and then performs a Model::find('count') on the currently configured datasource to ascertain the existence of the record in persistent storage.
Returns
True if such a record exists
field() public ¶
field( string $name , array $conditions = null , string $order = null )
Returns the contents of a single field given the supplied conditions, in the supplied order.
Parameters
- string $name
- Name of field to get
- array $conditions optional null
- SQL conditions (defaults to NULL)
- string $order optional null
- SQL ORDER BY fragment
Returns
field contents, or false if not found
Link
find() public ¶
find( array $conditions = null , mixed $fields = array() , string $order = null , integer $recursive = null )
Queries the datasource and returns a result set array.
Also used to perform new-notation finds, where the first argument is type of find operation to perform (all / first / count / neighbors / list / threaded ), second parameter options for finding ( indexed array, including: 'conditions', 'limit', 'recursive', 'page', 'fields', 'offset', 'order')
Eg: {{{ find('all', array( 'conditions' => array('name' => 'Thomas Anderson'), 'fields' => array('name', 'email'), 'order' => 'field3 DESC', 'recursive' => 2, 'group' => 'type' )); }}}
In addition to the standard query keys above, you can provide Datasource, and behavior specific keys. For example, when using a SQL based datasource you can use the joins key to specify additional joins that should be part of the query.
{{{
find('all', array(
'conditions' => array('name' => 'Thomas Anderson'),
'joins' => array(
array(
'alias' => 'Thought',
'table' => 'thoughts',
'type' => 'LEFT',
'conditions' => 'Thought.person_id = Person.id'
)
)
));
}}}
Behaviors and find types can also define custom finder keys which are passed into find().
Specifying 'fields' for new-notation 'list':
- If no fields are specified, then 'id' is used for key and 'model->displayField' is used for value.
- If a single field is specified, 'id' is used for key and specified field is used for value.
- If three fields are specified, they are used (in order) for key, value and group.
Otherwise, first and second fields are used for key and value.
Note: find(list) + database views have issues with MySQL 5.0. Try upgrading to MySQL 5.1 if you have issues with database views.
Parameters
- array $conditions optional null
SQL conditions array, or type of find operation (all / first / count / neighbors / list / threaded)
- mixed $fields optional array()
Either a single string of a field name, or an array of field names, or options for matching
- string $order optional null
- SQL ORDER BY conditions (e.g. "price DESC" or "name ASC")
- integer $recursive optional null
- The number of levels deep to fetch associated records
Returns
Array of records
Link
getAffectedRows() public ¶
getAffectedRows( )
Returns the number of rows affected by the last query.
Returns
Number of rows
getAssociated() public ¶
getAssociated( string $type = null )
Gets all the models with which this model is associated.
Parameters
- string $type optional null
- Only result associations of this type
Returns
Associations
getColumnType() public ¶
getColumnType( string $column )
Returns the column type of a column in the model.
Parameters
- string $column
- The name of the model column
Returns
Column type
getColumnTypes() public ¶
getColumnTypes( )
Returns an associative array of field names and column types.
Returns
Field types indexed by field name
getDataSource() public ¶
getDataSource( )
Gets the DataSource to which this model is bound. Not safe for use with some versions of PHP4, because this class is overloaded.
Returns
A DataSource object
getID() public ¶
getID( integer $list = 0 )
Returns the current record's ID
Parameters
- integer $list optional 0
- Index on which the composed ID is located
Returns
The ID of the current record, false if no ID
getInsertID() public ¶
getInsertID( )
Returns the ID of the last record this model inserted.
Returns
Last inserted ID
getLastInsertID() public ¶
getLastInsertID( )
Returns the ID of the last record this model inserted.
Returns
Last inserted ID
getNumRows() public ¶
getNumRows( )
Returns the number of rows returned from the last query.
Returns
Number of rows
getVirtualField() public ¶
getVirtualField( mixed $field = null )
Returns the expression for a model virtual field
Parameters
- mixed $field optional null
- $name Name of field to look for
Returns
If $field is string expression bound to virtual field $field If $field is null, returns an array of all model virtual fields or false if none $field exist.
hasAny() public ¶
hasAny( array $conditions = null )
Returns true if a record that meets given conditions exists.
Parameters
- array $conditions optional null
- SQL conditions array
Returns
True if such a record exists
hasField() public ¶
hasField( mixed $name , boolean $checkVirtual = false )
Returns true if the supplied field exists in the model's database table.
Parameters
- mixed $name
- Name of field to look for, or an array of names
- boolean $checkVirtual optional false
- checks if the field is declared as virtual
Returns
If $name is a string, returns a boolean indicating whether the field exists. If $name is an array of field names, returns the first field that exists, or false if none exist.
invalidFields() public ¶
invalidFields( string $options = array() )
Returns an array of fields that have failed validation. On the current model.
Parameters
- string $options optional array()
- An optional array of custom options to be made available in the beforeValidate callback
Returns
Array of invalid fields
See
Link
invalidate() public ¶
invalidate( string $field , mixed $value = true )
Marks a field as invalid, optionally setting the name of validation rule (in case of multiple validation for field) that was broken.
Parameters
- string $field
- The name of the field to invalidate
- mixed $value optional true
Name of validation rule that was not failed, or validation message to be returned. If no validation key is provided, defaults to true.
isForeignKey() public ¶
isForeignKey( string $field )
Returns true if given field name is a foreign key in this model.
Parameters
- string $field
- Returns true if the input string ends in "_id"
Returns
True if the field is a foreign key listed in the belongsTo array.
isUnique() public ¶
isUnique( array $fields , boolean $or = true )
Returns false if any fields passed match any (by default, all if $or = false) of their matching values.
Parameters
- array $fields
- Field/value pairs to search (if no values specified, they are pulled from $this->data)
- boolean $or optional true
- If false, all fields specified must match in order for a false return value
Returns
False if any records matching any fields are found
isVirtualField() public ¶
isVirtualField( mixed $field )
Returns true if the supplied field is a model Virtual Field
Parameters
- mixed $field
- $name Name of field to look for
Returns
indicating whether the field exists as a model virtual field.
joinModel() public ¶
joinModel( object $assoc , mixed $keys = array() , array $keys ,… )
Gets the name and fields to be used by a join model. This allows specifying join fields in the association definition.
Parameters
- object $assoc
- $model The model to be joined
- mixed $keys optional array()
- $with The 'with' key of the model association
- array $keys ,…
- Any join keys which must be merged with the keys queried
Returns
query() public ¶
query( string $sql ,… )
Returns a resultset for a given SQL statement. Custom SQL queries should be performed with this method.
Parameters
- string $sql ,…
- SQL statement
Returns
Resultset
Link
read() public ¶
read( mixed $fields = null , mixed $id = null )
Returns a list of fields from the database, and sets the current model data (Model::$data) with the record found.
Parameters
- mixed $fields optional null
- String of single fieldname, or an array of fieldnames.
- mixed $id optional null
- The ID of the record to read
Returns
Array of database fields, or false if not found
Link
resetAssociations() public ¶
resetAssociations( )
This resets the association arrays for the model back to those originally defined in the model. Normally called at the end of each call to Model::find()
Returns
Success
save() public ¶
save( array $data = null , mixed $validate = true , array $fieldList = array() )
Saves model data (based on white-list, if supplied) to the database. By default, validation occurs before save.
Parameters
- array $data optional null
- Data to save.
- mixed $validate optional true
Either a boolean, or an array. If a boolean, indicates whether or not to validate before saving. If an array, allows control of validate, callbacks, and fieldList
- array $fieldList optional array()
- List of fields to allow to be written
Returns
On success Model::$data if its not empty or true, false on failure
Link
saveAll() public ¶
saveAll( array $data = null , array $options = array() )
Saves multiple individual records for a single model; Also works with a single record, as well as all its associated records.
Options
- validate: Set to false to disable validation, true to validate each record before saving, 'first' to validate all records before any are saved (default), or 'only' to only validate the records, but not save them.
- atomic: If true (default), will attempt to save all records in a single transaction. Should be set to false if database/table does not support transactions.
- fieldList: Equivalent to the $fieldList parameter in Model::save()
Parameters
- array $data optional null
Record data to save. This can be either a numerically-indexed array (for saving multiple records of the same type), or an array indexed by association name.
- array $options optional array()
- Options to use when saving record data, See $options above.
Returns
If atomic: True on success, or false on failure. Otherwise: array similar to the $data array passed, but values are set to true/false depending on whether each record saved successfully.
Link
saveField() public ¶
saveField( string $name , mixed $value , array $validate = false )
Saves the value of a single field to the database, based on the current model ID.
Parameters
- string $name
- Name of the table field
- mixed $value
- Value of the field
- array $validate optional false
- See $options param in Model::save(). Does not respect 'fieldList' key if passed
Returns
See Model::save()
See
Link
schema() public ¶
schema( mixed $field = false )
Returns an array of table metadata (column names and types) from the database. $field => keys(type, null, default, key, length, extra)
Parameters
- mixed $field optional false
- Set to true to reload schema, or a string to return a specific field
Returns
Array of table metadata
set() public ¶
set( mixed $one , string $two = null )
This function does two things:
- it scans the array $one for the primary key, and if that's found, it sets the current id to the value of $one[id]. For all other keys than 'id' the keys and values of $one are copied to the 'data' property of this object.
- Returns an array with all of $one's keys and values. (Alternative indata: two strings, which are mangled to a one-item, two-dimensional array using $one for a key and $two as its value.)
Parameters
- mixed $one
- Array or string of data
- string $two optional null
- Value string for the alternative indata method
Returns
Data with all of $one's keys and values
Link
setDataSource() public ¶
setDataSource( string $dataSource = null )
Sets the DataSource to which this model is bound.
Parameters
- string $dataSource optional null
- The name of the DataSource, as defined in app/config/database.php
Returns
True on success
setInsertID() public ¶
setInsertID( mixed $id )
Sets the ID of the last record this model inserted
Parameters
- mixed $id
- inserted ID
setSource() public ¶
setSource( string $tableName )
Sets a custom table for your controller class. Used by your controller to select a database table.
Parameters
- string $tableName
- Name of the custom table
unbindModel() public ¶
unbindModel( array $params , boolean $reset = true )
Turn off associations on the fly.
If $reset is false, association will not be reset to the originals defined in the model
Example: Turn off the associated Model Support request, to temporarily lighten the User model:
$this->User->unbindModel( array('hasMany' => array('Supportrequest')) );
unbound models that are not made permanent will reset with the next call to Model::find()
Parameters
- array $params
- Set of bindings to unbind (indexed by binding type)
- boolean $reset optional true
- Set to false to make the unbinding permanent
Returns
Success
Link
updateAll() public ¶
updateAll( array $fields , mixed $conditions = true )
Updates multiple model records based on a set of conditions.
Parameters
- array $fields
Set of fields and values, indexed by fields. Fields are treated as SQL snippets, to insert literal values manually escape your data.
- mixed $conditions optional true
- Conditions to match, true for all records
Returns
True on success, false on failure
Link
updateCounterCache() public ¶
updateCounterCache( array $keys = array() , boolean $created = false )
Updates the counter cache of belongsTo associations after a save or delete operation
Parameters
- array $keys optional array()
- Optional foreign key data, defaults to the information $this->data
- boolean $created optional false
True if a new record was created, otherwise only associations with 'counterScope' defined get updated
validates() public ¶
validates( string $options = array() )
Returns true if all fields pass validation. Will validate hasAndBelongsToMany associations that use the 'with' key as well. Since __saveMulti is incapable of exiting a save operation.
Will validate the currently set data. Use Model::set() or Model::create() to set the active data.
Parameters
- string $options optional array()
- An optional array of custom options to be made available in the beforeValidate callback
Returns
True if there are no errors
Link
Methods inherited from Overloadable
Methods inherited from Object
Object() public ¶
Object( )
A hack to support __construct() on PHP 4 Hint: descendant classes have no PHP4 class_name() constructors, so this constructor gets called first and calls the top-layer __construct() which (if present) should call parent::__construct()
Returns
__openPersistent() public ¶
__openPersistent( string $name , string $type = null )
Open the persistent class file for reading Used by Object::_persist()
Parameters
- string $name
- Name of persisted class
- string $type optional null
- Type of persistance (e.g: registry)
_persist() public ¶
_persist( string $name , string $return , $object , $type = null )
Checks for a persistent class file, if found file is opened and true returned If file is not found a file is created and false returned If used in other locations of the model you should choose a unique name for the persistent file There are many uses for this method, see manual for examples
Parameters
- string $name
- name of the class to persist
- string $return
- $object the object to persist
- $object
- $type optional null
Returns
Success
_savePersistent() public ¶
_savePersistent( string $name , object $object )
You should choose a unique name for the persistent file
There are many uses for this method, see manual for examples
Parameters
- string $name
- name used for object to cache
- object $object
- the object to persist
Returns
true on save, throws error if file can not be created
_set() public ¶
_set( array $properties = array() )
Allows setting of multiple properties of the object in a single line of code. Will only set properties that are part of a class declaration.
Parameters
- array $properties optional array()
- An associative array containing properties and corresponding values.
_stop() public ¶
_stop( $status = 0 )
Stop execution of the current script. Wraps exit() making testing easier.
Parameters
- $status optional 0
- http://php.net/exit for values
cakeError() public ¶
cakeError( string $method , array $messages = array() )
Used to report user friendly errors. If there is a file app/error.php or app/app_error.php this file will be loaded error.php is the AppError class it should extend ErrorHandler class.
Parameters
- string $method
- Method to be called in the error class (AppError or ErrorHandler classes)
- array $messages optional array()
- Message that is to be displayed by the error class
Returns
message
dispatchMethod() public ¶
dispatchMethod( string $method , array $params = array() )
Calls a method on this object with the given parameters. Provides an OO wrapper
for call_user_func_array
Parameters
- string $method
- Name of the method to call
- array $params optional array()
- Parameter list to use when calling $method
Returns
Returns the result of the method call
log() public ¶
log( string $msg , integer $type = LOG_ERROR )
Convience method to write a message to CakeLog. See CakeLog::write() for more information on writing to logs.
Parameters
- string $msg
- Log message
- integer $type optional LOG_ERROR
- Error type constant. Defined in app/config/core.php.
Returns
Success of log write
requestAction() public ¶
requestAction( mixed $url , array $extra = array() )
Calls a controller's method from any location. Can be used to connect controllers together or tie plugins into a main application. requestAction can be used to return rendered views or fetch the return value from controller actions.
Parameters
- mixed $url
- String or array-based url.
- array $extra optional array()
- if array includes the key "return" it sets the AutoRender to true.
Returns
Boolean true or false on success/failure, or contents of rendered action if 'return' is set in $extra.
toString() public ¶
toString( )
Object-to-string conversion. Each class can override this method as necessary.
Returns
The name of this class