SessionHandler::read

(PHP 5 >= 5.4.0, PHP 7)

SessionHandler::readRead session data

说明

public string SessionHandler::read ( string $session_id )

Reads the session data from the session storage, and returns the result back to PHP for internal processing. This method is called automatically by PHP when a session is started (either automatically or explicity with session_start() and is preceeded by an internal call to the SessionHandler::open().

This method wraps the internal PHP save handler defined in the session.save_handler ini setting that was set before this handler was set by session_set_save_handler().

If this class is extended by inheritiance, calling the parent read method will invoke the wrapper for this method and therefor invoke the associated internal callback. This allows the method to be overidden and or intercepted and filtered (for example, decrypting $data value returned by the parent read method).

For more information on what this method is expected to do, please refer to the documentation at SessionHandlerInterface::read().

参数

session_id

The session id to read data for.

返回值

Returns an encoded string of the read data. If nothing was read, it must return an empty string. Note this value is returned internally to PHP for processing.

参见