To access and update ALI preferences using the .NET Portlet
Toolkit, use preference attributes or a preference collection.
Preference attributes provide type specific read-write
binding of an ALI preference to a page member variable (field). One
of the following access modifiers is required on all local fields
that are bound to a preference using a preference attribute: [protected
| internal | protected internal | public]. The modifier “private”
is not supported. Since this is the default modifier for a field if
none is specified, the modifier must not be omitted. Preference attributes
can be bound to fields with types of String, int, float, bool, or
DateTime. Values for fields marked with preference attributes are
set after the OnLoad() page event; any changes are persisted during
the OnUnload() page event.
ALIPortletPageexposes
a preference attribute for each type of preference:
PortletPreferenceAttribute,
CommunityPreferenceAttribute,
CommunityPortletPreferenceAttribute,
AdminPreferenceAttribute,
UserPreferenceAttribute, and
SessionPreferenceAttribute. All preference
attributes have two optional properties:
- Key: A string that provides the key name of the property
to which the member variable is bound. If you do not include this
property, the name of the preference defaults to the name of the variable.
Key values must be unique within a page.
- DefaultValue: A string that provides the value to use when the
preference is unavailable or has not yet been set.
Note: Private variables (including those with no permissions
modifier) cannot be seen by reflection and are not supported. You
must include a permissions modifier of public, protected or internal.
[PortletPreference]
protected int myIntPref;
[PortletPreference(Key = "lastAccessed", DefaultValue = "2008-01-01")]
protected DateTime lastAccessedDateTime;
Preference
collections allow you to enumerate all of the preference values
in the request using the PreferenceCollection.Keys property. ALIPortletPage provides a preference collection for each
type of preference: PortletPreferences, CommunityPreferences, CommunityPortletPreferences, AdminPreferences, UserPreferences, and SessionPreferences.
String myPrefValue = this.PortletPreferences["MyPrefName"];
this.PortletPreferences["MyPrefName"] = myPrefValue;
The examples above use PortletAttribute and PortletPreferences, but could be replaced
with Admin*, User*, Community*, CommunityPortlet* or Session* to read
preferences of the corresponding type. (Most preferences can also
be set from a portlet page, but Admin preferences must be set from
an preference page.)
For a full description of the API, see the complete class
documentation for the ALI section of the Portlet API, installed into
the Microsoft Visual Studio 2005 Integrated Help System.
For details
on the types of preferences available in ALI, see
Portlet Settings and Preferences in the ALI
6.0 development documentation.
