HeaderCollection

API reference › yii › web › HeaderCollection

class	`yii\web\HeaderCollection`
Extends	`yii\base\BaseObject`
Implements	`IteratorAggregate`, `ArrayAccess`, `Countable`, `yii\base\Configurable`
Since	2.0
Source	`framework/web/HeaderCollection.php`

HeaderCollection is used by Response to maintain the currently registered HTTP headers.

Properties

Property	Type	Description	Defined by
`$count` read-only	`int`	The number of headers in the collection.	`HeaderCollection`
`$iterator` read-only	`ArrayIterator<string, string[]>`	An iterator for traversing the headers in the collection.	`HeaderCollection`

Methods

Method	Description	Defined by
`__construct()`	Constructor.	`yii\base\BaseObject`
`__call()`	Calls the named method which is not a class method.	`yii\base\BaseObject`
`__get()`	Returns the value of an object property.	`yii\base\BaseObject`
`__isset()`	Checks if a property is set, i.e. defined and not null.	`yii\base\BaseObject`
`__set()`	Sets value of an object property.	`yii\base\BaseObject`
`__unset()`	Sets an object property to null.	`yii\base\BaseObject`
`add()`	Adds a new header.	`HeaderCollection`
`canGetProperty()`	Returns a value indicating whether a property can be read.	`yii\base\BaseObject`
`canSetProperty()`	Returns a value indicating whether a property can be set.	`yii\base\BaseObject`
`className()` static	Returns the fully qualified name of this class.	`yii\base\BaseObject`
`count()`	Returns the number of headers in the collection.	`HeaderCollection`
`fromArray()`	Populates the header collection from an array.	`HeaderCollection`
`get()`	Returns the named header(s).	`HeaderCollection`
`getCount()`	Returns the number of headers in the collection.	`HeaderCollection`
`getIterator()`	Returns an iterator for traversing the headers in the collection.	`HeaderCollection`
`has()`	Returns a value indicating whether the named header exists.	`HeaderCollection`
`hasMethod()`	Returns a value indicating whether a method is defined.	`yii\base\BaseObject`
`hasProperty()`	Returns a value indicating whether a property is defined.	`yii\base\BaseObject`
`init()`	Initializes the object.	`yii\base\BaseObject`
`offsetExists()`	Returns whether there is a header with the specified name.	`HeaderCollection`
`offsetGet()`	Returns the header with the specified name.	`HeaderCollection`
`offsetSet()`	Adds the header to the collection.	`HeaderCollection`
`offsetUnset()`	Removes the named header.	`HeaderCollection`
`remove()`	Removes a header.	`HeaderCollection`
`removeAll()`	Removes all headers.	`HeaderCollection`
`set()`	Adds a new header.	`HeaderCollection`
`setDefault()`	Sets a new header only if it does not exist yet.	`HeaderCollection`
`toArray()`	Returns the collection as a PHP array.	`HeaderCollection`
`toOriginalArray()`	Returns the collection as a PHP array but instead of using normalized header names as keys (like `toArray()`) it uses original header names (case-sensitive).	`HeaderCollection`

Method details

add()

public function add(string $name, string $value): $this

Adds a new header.

If there is already a header with the same name, the new one will be appended to it instead of replacing it.

Parameters

Parameter	Type	Description
`$name`	`string`	The name of the header
`$value`	`string`	The value of the header

Returns

$this: The collection object itself

count()

public function count(): int

Returns the number of headers in the collection.

This method is required by the SPL Countable interface. It will be implicitly called when you use count($collection).

Returns

int: The number of headers in the collection.

fromArray()

public function fromArray(array $array): mixed

Populates the header collection from an array.

Parameters

Parameter	Type	Description
`$array`	`array`	The headers to populate from

Returns

mixed

Since

2.0.3

get()

public function get(string $name, ($first is true ? string|null : string[]|null) $default = null, bool $first = true): ($first is true ? string|null : string[]|null)

Returns the named header(s).

Parameters

Parameter	Type	Description
`$name`	`string`	The name of the header to return
`$default`	`($first is true ? string\|null : string[]\|null)`	The value to return in case the named header does not exist
`$first`	`bool`	Whether to only return the first header of the specified name. If false, all headers of the specified name will be returned.

Returns

($first is true ? string|null : string[]|null): The named header(s). If $first is true, a string will be returned; If $first is false, an array will be returned.

getCount()

public function getCount(): int

Returns the number of headers in the collection.

Returns

int: The number of headers in the collection.

getIterator()

public function getIterator(): ArrayIterator<string, string[]>

Returns an iterator for traversing the headers in the collection.

This method is required by the SPL interface IteratorAggregate. It will be implicitly called when you use foreach to traverse the collection.

Returns

ArrayIterator<string, string[]>: An iterator for traversing the headers in the collection.

has()

public function has(string $name): bool

Returns a value indicating whether the named header exists.

Parameters

Parameter	Type	Description
`$name`	`string`	The name of the header

Returns

bool: Whether the named header exists

offsetExists()

public function offsetExists(string $name): bool

Returns whether there is a header with the specified name.

This method is required by the SPL interface ArrayAccess. It is implicitly called when you use something like isset($collection[$name]).

Parameters

Parameter	Type	Description
`$name`	`string`	The header name

Returns

bool: Whether the named header exists

offsetGet()

public function offsetGet(string $name): string|null

Returns the header with the specified name.

This method is required by the SPL interface ArrayAccess. It is implicitly called when you use something like $header = $collection[$name];. This is equivalent to get().

Parameters

Parameter	Type	Description
`$name`	`string`	The header name

Returns

string|null: The header value with the specified name, null if the named header does not exist.

offsetSet()

public function offsetSet(string $name, string $value): mixed

Adds the header to the collection.

This method is required by the SPL interface ArrayAccess. It is implicitly called when you use something like $collection[$name] = $header;. This is equivalent to add().

Parameters

Parameter	Type	Description
`$name`	`string`	The header name
`$value`	`string`	The header value to be added

Returns

mixed

offsetUnset()

public function offsetUnset(string $name): mixed

Removes the named header.

This method is required by the SPL interface ArrayAccess. It is implicitly called when you use something like unset($collection[$name]). This is equivalent to remove().

Parameters

Parameter	Type	Description
`$name`	`string`	The header name

Returns

mixed

remove()

public function remove(string $name): array|null

Removes a header.

Parameters

Parameter	Type	Description
`$name`	`string`	The name of the header to be removed.

Returns

array|null: The value of the removed header. Null is returned if the header does not exist.

removeAll()

public function removeAll(): mixed

Removes all headers.

Returns

mixed

set()

public function set(string $name, string $value = ''): $this

Adds a new header.

If there is already a header with the same name, it will be replaced.

Parameters

Parameter	Type	Description
`$name`	`string`	The name of the header
`$value`	`string`	The value of the header

Returns

$this: The collection object itself

setDefault()

public function setDefault(string $name, string $value): $this

Sets a new header only if it does not exist yet.

If there is already a header with the same name, the new one will be ignored.

Parameters

Parameter	Type	Description
`$name`	`string`	The name of the header
`$value`	`string`	The value of the header

Returns

$this: The collection object itself

toArray()

public function toArray(): array

Returns the collection as a PHP array.

Returns

array: The array representation of the collection. The array keys are header names, and the array values are the corresponding header values.

toOriginalArray()

public function toOriginalArray(): array

Returns the collection as a PHP array but instead of using normalized header names as keys (like toArray()) it uses original header names (case-sensitive).

Returns

array: The array representation of the collection.

Since

2.0.45