Basic Usage
Zend_Session_Namespace instances provide the primary
API for manipulating session data in the Zend Framework. Namespaces are
used to segregate all session data, although a default namespace exists for those who only
want one namespace for all their session data. Zend_Session utilizes
ext/session and its special $_SESSION superglobal as the storage
mechanism for session state data. while $_SESSION is still available in
PHP's global namespace, developers should refrain from directly accessing
it, so that Zend_Session and
Zend_Session_Namespace can most effectively and securely provide its
suite of session related functionality.
Each instance of Zend_Session_Namespace corresponds to an entry of
the $_SESSION superglobal array, where the namespace is used as the key.
It is possible to use Zend_Session in conjunction with other code
that uses $_SESSION directly. To avoid problems, however, it is highly
recommended that such code only uses parts of $_SESSION that do not
correspond to instances of Zend_Session_Namespace.
Tutorial Examples
If no namespace is specified when instantiating
Zend_Session_Namespace, all data will be transparently stored in
a namespace called "Default". Zend_Session is not
intended to work directly on the contents of session namespace containers. Instead, we
use Zend_Session_Namespace. The example below demonstrates use of
this default namespace, showing how to count the number of client requests during a
session:
Counting Page Views
numberOfPageRequests)) {
// this will increment for each page load.
$defaultNamespace->numberOfPageRequests++;
} else {
$defaultNamespace->numberOfPageRequests = 1; // first time
}
echo "Page requests this session: ",
$defaultNamespace->numberOfPageRequests;
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When multiple modules use instances of Zend_Session_Namespace
having different namespaces, each module obtains data encapsulation for its session
data. The Zend_Session_Namespace constructor can be passed an
optional $namespace argument, which allows developers to partition
session data into separate namespaces. Namespacing provides an effective and popular way
to secure session state data against changes due to accidental naming collisions.
Namespace names are restricted to character sequences represented as non-empty
PHP strings that do not begin with an underscore ("_")
character. Only core components included in Zend Framework should use namespace names
starting with "Zend".
New Way: Namespaces Avoid Collisions
user = "myusername";
// in a web services component
$webServiceNamespace = new Zend_Session_Namespace('Some_Web_Service');
$webServiceNamespace->user = "mywebusername";
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The example above achieves the same effect as the code below, except that the session
objects above preserve encapsulation of session data within their respective namespaces.
Old Way: PHP Session Access
Iterating Over Session Namespaces
Zend_Session_Namespace provides the full IteratorAggregate
interface, including support for the foreach statement:
Session Iteration
$value) {
echo "aNamespace->$index = '$value';\n";
}
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Accessors for Session Namespaces
Zend_Session_Namespace implements the
__get(), __set(),
__isset(), and __unset() magic
methods, which should not be invoked directly, except from within a
subclass. Instead, the normal operators automatically invoke these methods, such as in
the following example:
Accessing Session Data
foo = 100;
echo "\$namespace->foo = $namespace->foo\n";
if (!isset($namespace->bar)) {
echo "\$namespace->bar not set\n";
}
unset($namespace->foo);
]]>