prefmanager.php

来自「视频监控网络部分的协议ddns,的模块的实现代码,请大家大胆指正.」· PHP 代码 · 共 427 行 · 第 1/2 页

                $this->_lastError = "DB Error: ".$result->getMessage();
                return NULL;
            } else if ($result->numRows()) {
                // The query found a value, so we can cache that, and then return it.
                $row = $result->fetchRow(DB_FETCHMODE_ASSOC);
                $_SESSION[$this->_cacheName][$user_id][$pref_id] = $this->_unpack($row[$this->_valueColumn]);
                return $_SESSION[$this->_cacheName][$user_id][$pref_id];
            } else if ($this->_returnDefaults && $showDefaults) {
                // I was doing this with a call to getPref again, but it threw things into an
                // infinite loop if the default value didn't exist. If you can fix that, it would
                // be great ;)
                if (isset($_SESSION[$this->_cacheName][$this->_defaultUser][$pref_id]) && $this->_useCache) {
                    $_SESSION[$this->_cacheName][$user_id][$pref_id] = $_SESSION[$this->_cacheName][$this->_defaultUser][$pref_id];
                    return $_SESSION[$this->_cacheName][$this->_defaultUser][$pref_id];
                } else {
                    $query = sprintf("SELECT * FROM %s WHERE %s=%s AND %s=%s", $this->_table,
                                                                               $this->_userColumn,
                                                                               $this->_db->quote($this->_defaultUser),
                                                                               $this->_nameColumn,
                                                                               $this->_db->quote($pref_id));
                    $result = $this->_db->query($query);
                    if (DB::isError($result)) {
                        $this->_lastError = "DB Error: ".$result->getMessage();
                        return NULL;
                    } else {
                        if ($result->numRows()) {
                            $row = $result->fetchRow(DB_FETCHMODE_ASSOC);
                            $_SESSION[$this->_cacheName][$this->_defaultUser][$pref_id] = $this->_unpack($row[$this->_valueColumn]);
                            $_SESSION[$this->_cacheName][$user_id][$pref_id] = $_SESSION[$this->_cacheName][$this->_defaultUser][$pref_id];
                            return $_SESSION[$this->_cacheName][$user_id][$pref_id];
                        } else {
                            return NULL;
                        }
                    }
                }
            } else {
                // We've used up all the resources we're allowed to search, so return a NULL.
                return NULL;
            }
        }
    }

    /**
    * A shortcut function for getPref($this->_defaultUser, $pref_id, $value),
    * useful if you have a logged in user, but want to get defaults anyway.
    *
    * @param string $pref_id The name of the preference to get.
    * @return mixed The value if it's found, or NULL if it isn't.
    * @access public
    */
    function getDefaultPref($pref_id)
    {
        return $this->getPref($this->_defaultUser, $pref_id);
    }

    /**
     * Set a preference for the specified user.
     * 
     * @param string $user_id The user to set for.
     * @param string $pref_id The preference to set.
     * @param mixed $value The value it should be set to.
     * @return bool Sucess or failure.
     * @access public
     */
    function setPref($user_id, $pref_id, $value)
    {
        // Start off by checking if the preference is already set (if it is we need to do
        // an UPDATE, if not, it's an INSERT.
        if ($this->_exists($user_id, $pref_id, false)) {
            $query = sprintf("UPDATE %s SET %s=%s WHERE %s=%s AND %s=%s", $this->_table,
                                                                          $this->_valueColumnQuoted,
                                                                          $this->_db->quote($this->_pack($value)),
                                                                          $this->_userColumn,
                                                                          $this->_db->quote($user_id),
                                                                          $this->_nameColumn,
                                                                          $this->_db->quote($pref_id));
        } else {
            $query = sprintf("INSERT INTO %s (%s, %s, %s) VALUES(%s, %s, %s)", $this->_table,
                                                                               $this->_userColumn,
                                                                               $this->_nameColumn,
                                                                               $this->_valueColumnQuoted,
                                                                               $this->_db->quote($user_id),
                                                                               $this->_db->quote($pref_id),
                                                                               $this->_db->quote($this->_pack($value)));
        }
        $result = $this->_db->query($query);
        if (DB::isError($result)) {
            $this->_lastError = "DB Error: ".$result->getMessage();
            return false;
        } else {
	    if ($this->_useCache) {
	        $_SESSION[$this->_cacheName][$user_id][$pref_id] = $value;
	    }
            return true;
        }
    }

    /**
    * A shortcut function for setPref($this->_defaultUser, $pref_id, $value)
    *
    * @param string $pref_id The name of the preference to set.
    * @param mixed $value The value to set it to.
    * @return bool Sucess or failure.
    * @access public
    */
    function setDefaultPref($pref_id, $value)
    {
        return $this->setPref($this->_defaultUser, $pref_id, $value);
    }

    /**
    * Deletes a preference for the specified user.
    * 
    * @param string $user_id The userid of the user to delete from.
    * @param string $pref_id The preference to delete.
    * @return bool Success/Failure
    * @access public
    */
    function deletePref($user_id, $pref_id)
    {
        if ($this->getPref($user_id, $pref_id) == NULL) {
            // The user doesn't have this variable anyway ;)
            return true;
        } else {
            $query = sprintf("DELETE FROM %s WHERE %s=%s AND %s=%s", $this->_table,
                                                                     $this->_userColumn,
                                                                     $this->_db->quote($user_id),
                                                                     $this->_nameColumn,
                                                                     $this->_db->quote($pref_id));
            $result = $this->_db->query($query);
            if (DB::isError($result)) {
                $this->_lastError = "DB Error: ".$result->getMessage();
                return false;
            } else {
				if ($this->_useCache) {
				    unset($_SESSION[$this->_cacheName][$user_id][$pref_id]);
				}
                return true;
            }
        }
    }

    /**
    * Deletes a preference for the default user.
    * 
    * @param string $pref_id The preference to delete.
    * @return bool Success/Failure
    * @access public
    */
    function deleteDefaultPref($pref_id)
    {
        return $this->deletePref($this->_defaultUser, $pref_id);
    }
	
    /**
     * Checks if a preference exists in the database.  
     *
     * @param string $user_id The userid of the preference owner.
     * @param string $pref_id The preference to check for.
     * @return bool True if the preference exists.
     * @access private
     */
    function _exists($user_id, $pref_id)
    {
        $query = sprintf("SELECT COUNT(%s) FROM %s WHERE %s=%s AND %s=%s", $this->_nameColumn,
                                                                           $this->_table,
                                                                           $this->_userColumn,
                                                                           $this->_db->quoteSmart($user_id),
                                                                           $this->_nameColumn,
                                                                           $this->_db->quote($pref_id));
        $result = $this->_db->getOne($query);
        if (DB::isError($result)) {
            $this->_lastError = "DB Error: ".$result->getMessage();
            return false;
        } else {
            return (bool)$result;
        }
    }

    /**
     * Does anything needed to prepare a value for saving in the database.
     *
     * @param mixed $value The value to be saved.
     * @return string The value in a format valid for saving to the database.
     * @access private
     */
    function _pack($value)
    {
        if ($this->_serialize) {
            return serialize($value);
        } else {
            return $value;
        }
    }
    
    /**
     * Does anything needed to create a value of the preference, such as unserializing.
     *
     * @param string $value The value of the preference.
     * @return mixed The unpacked version of the preference.
     * @access private
     */
    function _unpack($value)
    {
        if ($this->_serialize) {
            return unserialize($value);
        } else {
            return $value;
        }
    }
}
?>