Personalization with ASP

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					Personalization with ASP.NET 2.0

Jayesh Patel, Bryan Acker, Robert McGovern

Infusion Development


July 2004


Applies to:

  ASP.NET 2.0

  ASP.NET framework

  Visual Studio 2005


Summary: Create personalized applications faster and build entirely new classes of applications with the

new personalization features in ASP.NET 2.0. (21 printed pages)


Contents


Introduction

Identifying and Managing Users

Creating a Custom User Experience

A Simple Web Part

A Derived WebPart

Implementing Interfaces

Storing User Data with Providers

Custom Membership Provider

Custom Profile Provider

Custom Personalization Provider

Conclusion


Introduction

The variety of business solutions that can now be serviced by Web based applications is continually

increasing. With added functionality and faster network connectivity, the infrastructure of the Internet

now supports increasing numbers and types of users. These users access the Internet for varying

reasons through many different devices, making the traditional 'anonymous' single user Web

architecture insufficient.


To keep pace with the new demands for more flexible, user-oriented Web applications, Microsoft

ASP.NET 2.0 includes an extensive personalization framework. The ASP.NET 2.0 personalization features

include new mechanisms for identifying and registering users, tailoring a Website to a specific user, and

storing user information automatically and transparently. Web Parts empower the user to include the

information they deem most valuable. Through layout control and inclusion of relevant tools, users can
create a site that streamlines their experience. These customizations can be persisted and made

available to those users on subsequent visits to the site.


This white paper provides a technical overview of new features, including Web Parts, authentication

controls, and personalization providers. If you are a beginning or mid-level developer, or just interested

in the new personalization features of ASP.NET 2.0, you will benefit from the code examples and feature

descriptions in this white paper.


The Personalization Process

Web sites have traditionally been used to convey information to interested viewers. A given site would

contain related information about a concept or product, and provide the added benefit of links to other

sources of relevant information. Web sites today serve a much broader purpose; the term portal, or

centralized information point, describes today's Web sites more accurately. It is in these types of sites

that personalization features, such as Web Parts and the Profile service, can be leveraged to provide

viewers with a configurable and relevant Web experience. As companies grow in size and complexity,

information must be delivered in a controlled and secure manner. In order for a Website to provide a

personalized experience, the Web application must perform several distinct tasks:


        Identify the user—A Web application must have a mechanism for separating the requests of one

    user from another. Identifying the user and associating the user with specific roles involves three

    distinct processes: First, the Website must have a means for allowing a user to identify himself

    (authentication); second, the Website must also have a means for identifying the user's requests

    (session continuity); finally, the Website must have a mechanism for creating and managing new

    user identities.

        Provide a personalized experience—Personalizing a Web experience can range from allowing or

    disallowing functions for a particular user (authorization), providing a user with a custom display, or

    keeping track of user information (for example, a shopping cart). All of these tasks leverage the

    user's identity in a different way, to provide a Web experience that is specific for each user.

        Store user information—In most cases, a Web application will need to store user information

    between requests or between sessions. User information can range from the user's identity (login

    and password) to a complex preference list or historical data (Amazon's "wish list," for example).

One of the challenges in developing personalized Web applications has been designing the framework

code necessary to support the personalization process. Not only do you have to develop each function,

you have to ensure that all of the functions work together in a secure and seamless fashion.


ASP .NET 2.0 introduces a series of new controls and technologies that provide an elegant solution to

these issues, and if the default functionality is not suitable the provider framework allows for the

development of custom solutions that work seamlessly with other aspects of the system.
Personalization in ASP.NET 2.0

ASP.NET 2.0 greatly simplifies and enhances personalization by providing integrated controls and

functions, which are designed specifically to support each phase of the personalization process. From an

ASP.NET 2.0 perspective, the three main areas of personalization support are membership, profiles, and

Web Parts. In this white paper, we will examine each of these areas in greater detail.


Membership


ASP.NET 1.x provided authentication and authorization services that relied on external data stores or

configuration in the web.config file. For example, an ASP.NET 1.1 application could provide forms-based

authentication, which required that the developer create a login form and associated controls to acquire,

validate, and manage user credentials. Once the user was authenticated, authorization was provided

through XML configurations in the web.config file.


ASP.NET 2.0 expands on these services in three distinct ways:


          Login and User controls—The new suite of login and user management controls reduce the need

    to rewrite standard user code for each application. You can, for example, create a set of pages for

    registering a new user, allowing an existing user to login, and even send a forgotten password to a

    user simply by placing the appropriate controls on the page and setting a few properties.

          User management—Each ASP.NET 2.0 application can be accessed through a special set of

    administrative pages, which allow an authorized user to create new users, assign users to roles, and

    store user information. If you want to write your own management tools, you can access all of the

    same features programmatically.

          Membership Provider—The membership feature creates a link between the front end features

    (login controls and user management site) and the persistence mechanism. A membership provider

    encapsulates all the data access code that is required to store and retrieve users and roles. Thanks

    to the provider model, this component can easily be replaced with a provider that supports your

    particular data source.

These three components work together to reduce the amount of code that is required to provide

membership services and link the membership services to a persistent data store.


Profiles


In ASP.NET 1.x applications, user specific data was often stored in the session and persisted to a

database when necessary. This process was often inefficient, and required the development of special

framework code.


ASP.NET 2.0 helps solve this problem by providing a new profile service. A profile is simply a set of data

that is associated with each user. The profile can contain any serializable data type from basic data types
(string, int, and the rest) to complex objects. Unlike in ASP.NET 1.x, the management of the profile is

automatic. ASP.NET 2.0 takes care of creating and storing the user profile automatically.


The heart of the profile service is the profile provider. The profile provider contains all the code and

structure necessary to persist and load user data to a data store. Similar to the membership provider, the

profile provider is designed so that you can replace it with a provider that matches your choice of data

store.


Web Parts


The Web Parts framework is a highly advanced replacement for portal based Web sites that use HTML

frames. Basically, you can use Web Parts to create a multi-component application, where the user can

decide which components to display, how to configure the components, and how to arrange the

components on the page. Once authenticated users have set up the Web Parts the way they want them,

the layout is automatically preserved between sessions. In other words, Web Parts let you build Web

applications that look and act like a desktop.


Web Parts rely on a personalization provider to manage the persistence of Web Part layouts between

sessions. Once again, the provider is designed as an extensible part of the .NET framework. If you do not

want to use the providers available as part of the framework, you can easily create your own.


Identifying and Managing Users

The first step in personalizing a Website is establishing a mechanism for identifying and managing users.

As a Website user, you must have a means to identify yourself to the Website in order to access your

personalized content. As a Website administrator, you must have a means for registering new users,

assigning users to specific roles, deleting users, and responding to requests for lost passwords. All of

these functions have been greatly simplified with ASP.NET 2.0.


Identifying Users

Traditional Web application systems have leveraged a wide range of mechanisms for identifying a user.

In ASP.NET v1.0, for example, you could choose from one of four different authentication mechanisms,

ranging from Windows authentication to custom forms. Once you selected an authentication mechanism,

however, you still had to build your own code to support the user base, by creating new users, linking

users to roles, and evaluating the roles in your Website. Although technologies such as Windows

authentication and Active Directory helped solve the problem, the Web developer still had to write a lot

of code.


ASP.NET 2.0 builds on the base authentication mechanisms in two distinct ways. First, ASP.NET 2.0

includes a suite of new controls for building login and user management Web forms, and second,

ASP.NET 2.0 includes new APIs for creating user accounts and associating users with specific roles.
This table describes controls used to service identity related issues:


Name                                    Description

<asp:login>                             Standard login capability that allows users to enter credentials.

<asp:loginname>                         Display the name of the logged in user.

<asp:loginstatus>                       Specifies whether the user has been authenticated.

<asp:loginview>                         Provides various login views depending on selected template

<asp:passwordrecovery>                  Sends an e-mail message that supplies a lost password to the
                                        user.

<asp:CreateUserWizard>                  User creation wizard with declarative configuration.

<asp:ChangePassword>                    Password change wizard with declarative configuration.


The <asp:login> control creates the appropriate labels, text fields, and buttons to gather user

credentials. The look and feel of this control can be modified using a built in format, or it can be

configured using style sheets. The properties window also allows access to the label, value, and

validation message, as well; the login button's appearance can be modified to suit individual needs.


The <asp:passwordrecovery> control reduces the amount of developer code required to handle

situations where a password is lost or forgotten. Using SMTP configured through the web.config file, the

password recovery control will send an e-mail message containing a user's password to an e-mail

address previously associated with the specified account.


User Management

To simplify the process of managing users, ASP.NET 2.0 provides a built in Website configuration tool.

The Website Administration Tool is a simple Website that can only be accessed through a secure

connection, or directly on the localhost. Through this tool an administrator can manage the application,

by configuring services such as user management, the personalization providers, security, and profiles.

The Website configuration tool provides a graphical front-end to a number of ASP .NET 2.0 technologies,

such as personalization, membership, and providers.


The membership API exposes user-management functionality, while the Profile objects handles

user-preference details. The membership API can also be accessed programmatically or through user

controls. For cases where a custom user-management interface is required, the Membership and

MembershipUser objects should be used to persist and retrieve user details. For most authentication

concerns, the login controls provide a very robust and configurable mechanism.


Personalization Provider
The personalization provider creates the link between the Web Parts feature that consumes

personalization data, and the data store that contains the user information. Through the Website

Administration Tool, you can configure a personalization provider and connect it to a SQL Server or

Access database.


The schema in Figure 1 is used by the ASP.NET 2.0 administration tool and the SQL Server

personalization provider:




Figure 1. Generated data model


This schema shows the data model that is used to store membership data for managing users on a

personalized Website. Note that the exact schema will depend on your provider.


Although ASP.NET 2.0 ships with providers for SQL Server and Microsoft Access, the provider framework

was designed for extensibility. Creating a provider for another database or even an XML file is simply a

matter of developing a new provider class and registering it with the administration tool.


Managing User Accounts


Once the provider has been configured and a data store has been created, the next step is to populate

the data store with user information. The Website Administration Tool has a simple create user form that

lets an administrator create a new user and send a password in an e-mail message to the user.
Figure 2. User creation—Website administration tool


Although this Web form is useful for creating small numbers of users, many Websites support hundreds

or thousands of registered users. Fortunately, the Website Administration Tool is just a Web-based shell

on top of the administration API. In other words, creating a batch user upload process or creating a

self-registration form for users is simply a matter of leveraging the proper ASP.NET 2.0 classes.


Programmatic User Creation


The membership API encapsulates all user maintenance functionality, and can be accessed through a

number of classes. The two most important membership classes are Membership and

MembershipUser.


The System.Web.Security.Membership class provides methods to create, delete, update, and find

users. To create a user account from within an application, simply call one of the CreateUser() methods

from the Membership class.


try {

      MembershipUser newUser = Membership.CreateUser("Seth", "trader");

} catch (MembershipCreateUserException mcue) {

      string error = mcue.Message;

}
In this case, the CreateUser method attempts to persist the new user using the underlying membership

provider. If a failure occurs, the CreateUser() method will throw a

MembershipCreateUserException indicating the problem. The exception can be queried for its

Message or StatusCode property to determine the exact nature of the failure.


For more functional error handling, you can use an overloaded version of CreateUser that accepts an

in/out MembershipCreateStatus enumeration, which will provide error codes for different types of

failure conditions.


MembershipCreateStatus status;

MembershipUser newUser = Membership.CreateUser(

      "Seth", "trader", "seth@boilerroom.com",

      "last name?", "Davis", true, out status);

if (status == MembershipCreateStatus.Success) {

      Server.Transfer("WebParts.aspx");

} else {

    //User creation failed, determine the failure type

      string errorcode;

      switch (status) {

       case MembershipCreateStatus.DuplicateUserName:

           errorcode = "Username already exists.";

           //resolve error condition and try again

           break;

       case MembershipCreateStatus.DuplicateEmail:

           // Other 8 conditions omitted for brevity

The MembershipCreateStatus enumeration is passed as an output parameter to the CreateUser

method. On method completion, the status object can be queried for error codes, and the results can be

compared against MembershipCreateStatus's predefined error types.


Once a user is successfully created, the user's details are encapsulated in a

System.Web.Security.MembershipUser class. The MembershipUser class can be used to
determine the date of last activity, modify a password or a password security question, modify comments

on the user, and approve or disable the user account.


Programmatic Role Assignment


Once a user has been created, the user can be added to a role through the

System.Web.Security.Roles object. Assigning a Role is as easy as linking the user name to the role

name.


Roles.AddUserToRole("Seth", "Administrator");

Note that ASP.NET users and roles aren't necessarily linked to Windows users and roles.


The Login Controls Revisited


Most of the functionality contained in the Membership, MembershipUser, and Roles classes is

encapsulated in the login controls. Using the login controls therefore saves you time and code when

developing user management. For example, using the Login controls and the new cross-page posting

feature, you can create a multi-step user registration process that gathers user information, verifies the

information, and then automatically creates the new user thanks to the login controls and the

membership provider.


Creating a Custom User Experience

Most traditional Web applications offer little in the way of a customized user experience, because of the

complexities involved with tracking, storing, and using the user's information for anything more than

simple text displays. With ASP.NET 2.0, however, you can quickly and easily create a user interface that

will display specific content, store user information, and allow the user to modify the display according to

his or her preferences.


Profiles

Profiles are a configurable mechanism for creating storable buckets of information for a specific user. A

profile can be used to store anything from the user's name to complex data objects. Profiles essentially

replace the persistence code required to gather user information, persist it to the session (or cookies or

database), and ensure that the information was maintained between user sessions.


The Profile object is configured using an XML Schema that is stored in the web.config file as an XML

element. Once a well formed profile configuration is saved into the web.config file, it is immediately

available to the IDE and runtime. A profile can be as simple or complex as is required by the application.


Defining a Profile


A profile is defined according to a specific set of XML tags in the web.config file. Each element in a profile

must be minimally specified with a name and usually a data type. If no type attribute is included, the
default type of string is assumed. Any type of data, from primitives to user-defined objects, can be

stored in a profile. Both the name and data type are used by Visual Studio 2005 to provide Intellisense

and perform runtime checking.


<profile>

    <property name="NumberOfApples" type="int" />

</profile>

The property created will be referenced by the name NumberOfApples, and will be an integer.


A property can also define additional attributes that define, among other things, how the profile element

will be saved, and whether the element will be used by anonymous users.


<profile>

    <property

         name="EmailAddresses"

         type="System.Collection.Specialized.StringCollection"

         serializeAs="Xml"

         allowAnonymous="false"

         provider="SQL"/>

       <property name="NumberOfApples" type="int" defaultValue="3" />

</profile>

This profile defines the EmailAddress property that makes use of many of the parameters available for

use by properties. This table outlines the complete list of attributes that can be applied to a given

property; most are optional.


Attribute Name             Optional?           Example            Description
                                               Values

name                       Required            String             A unique identifier for this property.

type                       Optional            Primitive |        A .NET primitive type or class. Class
                                               User Defined       names must be fully qualified (e.g.
                                               type               Myapp.UserData.ColorPrefs).

serializeAs                Optional            String | Xml |     Format of value when persisting in
                                               Binary             datastore.
allowAnonymous             Optional              true | false      Restrict or allow anonymous access to
                                                                   this value. If set to false, anonymous
                                                                   users won't have access to this profile
                                                                   value.

provider                   Optional              String            The provider used to manage this
                                                                   value. Overrides the defaultProvider
                                                                   setting in web.config or
                                                                   machine.config.

defaultValue               Optional              String            Value to return if property has not been
                                                                   explicitly set.

readOnly                   Optional              true | false      Restrict write access.


The provider attribute can play a crucial role in situations where different parts of the profile are stored

through different providers. For example, private user data may be stored through a database provider,

whereas less important (or easily reconstructed) data may be stored in an XML file. By assigning specific

providers, such scenarios are easily possible.


Grouping Properties


In many cases, a profile should be made up of a number of properties that are grouped together to

convey some type of business concern. For example, a group of related properties may represent user

preferences, where another group may represent billing information. In ASP.NET 2.0, properties can be

grouped together using the <group> tag.


<profile>

   <properties>

    <group name="Preferences">

      <add name="ShowQuoteOfTheDay"

       defaultValue="true" type="System.Boolean" />

      <add name="ShowNews" type="System.Boolean" />

    </group>

    <group name="BillingAddress">

      <add name="Street" type="System.String" />

      <add name="City" defaultValue="Toronto" type="System.String" />

      <add name="StateProv" type="System.String" />
      <add name="ZipPostal" type="System.String" />

    </group>

   </properties>

 </profile>

Note that each group must have a unique name, and that the elements within the group must be uniquely

named. Elements in different groups may share names, however, because the group association keeps

the elements distinct.


Accessing Profile Properties in Code


Once you have defined a profile in the web.config file, you can access the various profile elements

through the Profile object. This object is actually a special sub-class of

System.Web.Profile.HttpProfileBase that is created during page compilation. The Profile sub-class

automatically contains strongly typed access methods for all of the properties and groups defined in the

profile. The Profile object is therefore a custom class for each Web application. From a developer

perspective, however, Profile class creation is automatic and transparent.


The Profile object provides read and write access to the properties in the current user's profile. If a

property is contained within a group, the group acts like an additional property that in turn has

sub-properties. As a developer, you just program against the Profile object, and ASP.NET will

automatically handle loading and saving the Profile on your behalf.




Figure 3. Strongly typed web.config properties with Intellisense support


Visual Studio 2005 reflects changes to the web.config file immediately. Properties become accessible

through Intellisense as soon as the web.config file is saved. In other words, if you need to modify a profile

during development, Visual Studio 2005 will instantly recognize the change and provide appropriate tool

support.
Web Parts

Coupled with a WebPartManager and contained within WebPartZones, Web Parts are modular

components that can be included and arranged by the user to create a productive interface that is not

cluttered with unnecessary details. The user can:


        Choose which parts to display.


        Configure the parts in any order or arrangement.

        Save the view from one Web session to the next.

        Customize the look of certain Web Parts.

All of these features are practically impossible to implement with ordinary Web applications.


Web Part Architecture


You can think of Web Parts as modular Web page blocks. Each block can be added or removed from the

Web page dynamically, at runtime. Code for organizing and manipulating Web Parts is built into ASP.NET

2.0. All of the functionality for adding, removing, and configuring layout is automatically handled by the

Web Parts system. The programmer simply builds Web Parts and assigns them to Web Part Zones. A user

can mix and match Web Parts, display them in any order, and expect the configuration to be saved

between site visits. All the functionality of Web Parts, including adding, removing, and listing, is managed

automatically using a WebPartManager.


The key components of the Web Part framework are:


        The System.Web.UI.WebControls.WebParts.WebPart class—The WebPart is the base

    class outlining configuration properties that allow sub classes to be members of Web Part Zones.

    Generally, one or more controls will be encapsulated in a subclass of WebPart, or a

    GenericWebPart will be wrapped around a single user control.

        The System.Web.UI.WebControls.WebParts.WebPartZone control—The WebPartZone

    control is a wrapper around a collection of Web Parts. The WebPartZone provides the infrastructure

    for the Web Parts and is used to define the look and feel of the screen region occupied by the zone.

        The System.Web.UI.WebControls.WebParts.WebPartManager control—One

    WebPartManager is linked to each page that uses Web Parts. The WebPartManager configures

    and maintains the state of all Web Parts on the page.

These three controls combine together to create Web pages that are visually and functionally similar to

complex desktop applications.


Building Web Parts
A Web Part can be built in one of three ways. First, you can drop an ordinary user control onto a

WebPartZone. The user control will automatically be encapsulated in a GenericWebPart wrapper. This

method of Web Part creation is the easiest way to extend personalization to user controls.


Second, you can create a control that extends the WebPart class. You might want to use this approach

if you want to modify the behavior of the Web Part, or want to have greater control over Web Part

features and properties. You have to develop a server control, however, which requires more complex

code and development effort than using a GenericWebPart. Extending the basic WebPart class is often

a better choice than implementing the interfaces, since you automatically inherit the code for processing

verbs and user actions from working with a WebPartManager. Once you inherit the class, simply

overload the RenderContents() method to generate the content specific to your Web Part.


Third, you can implement the IWebPart and IWebActionable interfaces. The IWebPart interface

defines several methods related to how a WebPart works. The most important method is

RenderContents(), which allows you to generate the output for your Web Part. The IWebActionable

interface, on the other hand, defines how a Web Part has to support verbs and user actions.


A Simple Web Part

The easiest way to create a Web Part is to drag any user control onto an existing WebPartZone This

method allows for rapid development of Web Parts, and is well suited for the development of static

content. Though simple to create, this method of building Web Parts has a number of limitations. First,

each control that is added to a WebPartZone gets its own GenericWebPart wrapper. Thus, adding

multiple controls will result in the creation of many Web Parts. Second, the Web Part properties that

control advanced Web Part functionality are not available to generic Web Parts. If you do want to use the

GenericWebPart, your best approach is to create a single custom user control that contains all of your

smaller controls and content. Then you can drag and drop your custom control onto the WebPartZone

and create a single Web Part.


Note that you won't ever see the GenericWebPart wrapper. At runtime, the Web Part framework

automatically injects a GenericWebPart wrapper into the control tree. In other words, the mechanics of

creating this wrapper class around your user control are automatic, and performed behind the scenes by

the ASP.NET 2.0 compiler.


A Derived WebPart

To expose the full functionality of Web Parts, a custom Web Part can be created by extending the

WebPart class. The steps involved in creating a custom Web Part are similar to those required to build

a custom user or server control. First, create an object that extends the WebPart class.


using System;
using System.Text;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI;

namespace PartsLibrary {

      public class announcementControl : WebPart {

            public announcementControl() {}

            protected override void

                  RenderContents(HtmlTextWriter writer) {

                  writer.Write(

            "Dr. William K Chin discovers new treatment for Ranaud's!");

            }

      }

}

The code above creates a sub class of WebPart, and overrides the RenderContents() method to print

out a message. For simplicity sake, this example is relatively uneventful. An announcementControl

could encapsulate complex business logic in a real world scenario, however. Note that the class is defined

in the PartsLibrary namespace, and should be compiled into an assembly.


Next, add a reference to the assembly in the Web project where you want to use the

announcementControl Web Part. The Web Part can now be added to the pages of the application by

simply dragging and dropping it from the toolbox, or adding code directly to your ASPX page. The

following code illustrates the source required to register and instantiate our annoucementControl.


<%@ Register TagPrefix="jc1" Namespace="ClassLibrary1"
Assembly="ClassLibrary1" %>

…

    <asp:WebPartZone ID="BottomZone"

      Runat="server" Height="45px" Width="760px">

          <PartTitleStyle Font-Bold="True"

          BackColor="Black" ForeColor="DarkKhaki">
         </PartTitleStyle>

             <RestoreVerb ImageUrl="~/images/RestoreVerb.GIF">

             </RestoreVerb>

             <HeaderStyle BackColor="Black"

               ForeColor="DarkKhaki"></HeaderStyle>

             <MinimizeVerb ImageUrl="~/images/MinimizeVerb.GIF">

             </MinimizeVerb>

             <ZoneTemplate>

                   <jc1:announcementControl

                    Runat="server" ID="AnnouncementControl1"

                      ForeColor="#C00000"

                      BackColor="Silver" Title="Announcements"

                      AllowHide="False" AllowMinimize="False"

                      AllowClose="False" />

             </ZoneTemplate>

    </asp:WebPartZone>

The register-directive associates the jc1 prefix with our custom Web Part, thus making all controls (the

announcementControl) in the assembly available for use in this page. The custom Web Part

jc1:announcementControl is fully configurable, and exposes Web Part properties such as AllowHide

and AllowMinimize for configuration. These options are not available when using the simple Web Part

creation method.




Figure 4. Web Part with verb control


Note that the Announcements Web Part in Figure 4 does not make standard verbs available to the user.

In the code above, those properties were specifically disabled. By disabling certain Web Part features,

you can ensure that required page elements are not accidentally removed by the user.
Using this method of creating a Web Part also exposes more features, such as co-ordination with the

Personalization provider, to persist user-preference details across multiple site visits.


Implementing Interfaces

The last option for creating Web Parts is to implement the IWebPart and IWebActionable interfaces.

Directly implementing the interfaces allows a developer to modify the fundamental behavior of the Web

Parts framework. You should only use this method if you want to directly control every aspect of how the

Web Part works. In most cases, you should simply extend the WebPart class, and avoid rewriting all of

the Web Part functionality.


Web Part Zones


A Web Part Zone is a region of space that contains a collection of Web Parts. The Web Part Zone is a

container that defines properties that can be manipulated to change the look and feel of the components

within its contained scope.


Each Web Part Zone should contain the user-interface elements and controls required to fully complete

a given task. All Web Part Zones should also contain mutually exclusive functionality. By ensuring that

the functionality contained in each Web Part Zone is independent of all others, the developer relieves the

user from complex user-interface management concerns.


Web Part Zones are defined within the .aspx page using the <asp:WebPartZone> control tag. The code

below shows a typical Web Part Zone definition containing the announcements Web Part. Note that the

following code is not the complete .aspx page.


    <asp:WebPartZone ID="BottomZone" Runat="server"

         Height="45px" Width="760px">

         <PartTitleStyle Font-Bold="True"

            BackColor="Black" ForeColor="DarkKhaki">

         </PartTitleStyle>

              <RestoreVerb ImageUrl="~/images/RestoreVerb.GIF">

              </RestoreVerb>

              <HeaderStyle BackColor="Black" ForeColor="DarkKhaki">

              </HeaderStyle>

              <MinimizeVerb ImageUrl="~/images/MinimizeVerb.GIF">
             </MinimizeVerb>

             <ZoneTemplate>

                  <jc1:announcementControl Runat="server"

                   ID="AnnouncementControl1"

                       ForeColor="#C00000" BackColor="Silver"

                       Title="Announcements"

                       AllowHide="False" AllowMinimize="False"

                       AllowClose="False" />

             </ZoneTemplate>

      </asp:WebPartZone>

A Web Part Zone must be configured with a unique id attribute, which is used by the Web Part manager

control to identify a particular zone within the page. The title is displayed as a header for the Web Part

Zone when editing page layout.


Web Part Verbs


Web Part Verbs are user interface elements that enable users to perform specific Web Part related actions.

You can think of Web Part Verbs as being equivalent to the standard commands and icons found on most

desktop Windows applications. These verbs are defined by the WebPartZone, which provides a number

of standard verbs: Close, Minimize, Restore, Help, Edit, Connect, and Export.


Each verb can be configured as an XML element inside of the Web Part Zone.


<asp:WebPartZone id="Zone1"                 runat="Server">

   CloseVerb ImageUrl="images/CloseVerb.jpg"

                  Enabled="True"

                  Text="Close"

                  Description="Closes the WebPart"

                  visible="True" />

   <ZoneTemplate>

       <custom:QuoteWebPart title="Quotations"
         id="QuoteWebPart" runat="Server" />

   </ZoneTemplate>

</asp:WebPartZone>

A typical verb contains a number of parameters describing its state and visual composition. For example,

an image can be associated with the verb using the imageUrl attribute. Typically, the image is a small

icon style image that symbolizes the intended action.


Verbs are displayed in the upper right corner of the WebPartZone title bar. By default, the verb displays

as simple text. By assigning an icon, however, you can create custom displays of verbs.




Figure 5. Web Part Verbs


Verbs also have an associated tool tip that can be configured to give a textual description of the indented

task. Adding iconographic verbs to Web Parts can therefore reduce the amount of screen real-estate used

to convey common functionality.


Templates


Throughout ASP.NET 2.0, templates are used to configure common elements of user controls. The Web

Parts components also make use of templates to configure the look and feel of the Web Parts on the page.

Web Parts are added to a WebPartZone by placing them within the <ZoneTemplate> tag. The

ZoneTemplate defines the default layout of its constituent Web Parts.


<ZoneTemplate>

   <custom:DrugWebPart Title="Drugs" bgcolor="#333333"

    id="DrugWebPart1" runat="server" />

   <custom:ScheduleWebPart Title="Schedules"

    id="QuoteWebPart2" runat="server" />

   <custom:EventsWebPart Title="Daily Events"

    id="QuoteWebPart3" runat="server" />
</ZoneTemplate>

All of the parts stored within the same template will use the same look and feel. Note that the

CatalogZone and EditorZone also define a ZoneTemplate, and that the ZoneTemplate for these

zones may use a different look and feel than the standard Web Part Zones. You might, for example, want

to emphasize the catalog zone by having the look and feel change when the user enters catalog mode. By

using templated controls, ASP.NET 2.0 allows developers to define the look and feel of Web Parts

declaratively. Templates also promote a more consistent UI for controls, resulting in an improved user

experience with these interactive components.


Web Part Manager


One, and only one, Web Part manager must be added to any page that uses Web Parts. The manager

control must be added before any Web Part Zone, and is responsible for keeping track of the state of all

the Web Parts on the page.


The Web Part manager control's DisplayMode property is of particular interest, because it defines the

type of configuration options available to the end user. DisplayMode has several possible values.


        Catalog—Displays a list Web Parts and allows parts to be rearranged.

        Design—Allows the user to rearrange Web Parts on the page.

        Edit—Allows a user to edit specific attributes of individual Web Parts.

        Connect—Provides communication between two Web Parts

        Browse (default)—Displays the page with user preferences applied.

Using the different modes, developers can expose desired functionality to the user. For example, the

catalog mode depicted in Figure 6 lets the user select which Web Parts are displayed. In catalog mode,

the WebPartManager's catalog zone becomes visible to the user. Web Parts can be selected, and then

added, to one of the page's zones by using the add button. This is the only mode in which Web Parts can

be added to the page.
Figure 6. Catalog mode—Web Parts


A typical catalog will contain several different Web Parts, each of which displays specific information or

allows the user to access specific functions. For example, the catalog in Figure 6 is part of a Web Portal

for a hospital. Doctors, nurses, and administrators all use this portal to access scheduling information,

daily events, announcements, and patient status. The portal contains patient information, so security is

a definite concern. The portal therefore relies on the membership service to identify each user, and

determine which information to display.


Once the user has selected which parts to add to the zone, he can click the close button to switch back

to browse mode and see the resulting layout:




Figure 7. Browse mode—Web Parts
For example, Figure 7 shows a Web Part layout for Dr Jayesh Patel. Dr Patel has chosen to display Web

Parts for current patient list (upper left), drug lookup (lower left), and billing information (right).


A Web Part can be moved from one Web Part Zone to another using the ASP.NET built-in drag and drop

functionality. Dr Patel might decide, for example, to group the patient list and billing information on the

right hand side of the page.




Figure 8. Drag and Drop—Web


Figure 8 shows a Web Part being dragged from the leftzone to the mainzone. Any available Web Part can

be placed in any Web Part Zone. Once the part is relocated by the user, the state of the page is persisted

to secondary storage. On subsequent visits to the Website, the user's Web Part layout is recalled.


The Personalization Provider


Web Part layouts and configuration are stored by the personalization provider. This provider is similar to

the membership provider and profile provider, in that it transparently manages persisting user

information. The personalization provider is specific for storing Web Part configurations for each user,

however.


Storing User Data with Providers

The provider model is used throughout ASP.NET 2.0 as a mechanism to extend and enhance the

framework. The provider is therefore both a pattern and a point, where developers can extend the

ASP.NET 2.0 framework to meet specific needs. For example, a developer can create a new provider to

support the user identification system, or to store personalization data in an alternate data store.


Most custom providers will interact with database backend systems. The programmer is free to

implement the required provider methods and classes, however, using any medium or algorithm, so long

as they meets the model's required interface specification.
The Provider Model

The provider model is derived from a number of widely accepted patterns. The model defines a set of

classes and hooks to the data persistence layer that provides storage and retrieval for specified requests.

In this way, the provider model acts as a programming specification that allows ASP.NET 2.0 to service

unique client concerns.


With respect to personalization, ASP.NET 2.0 uses three different providers:


        Membership—The membership provider supports user-authentication and user-management.


        Profile—The profile provider supports the storage and retrieval of user-specific data linked to a

    profile.

        Personalization—The personalization provider supports the persistence of Web Part

    configurations and layouts for each user.

Each type of provider acts independently of the other providers. You can therefore replace the profile

provider without causing problems with the membership provider.


Choosing from Existing Providers


ASP.NET 2.0 ships with two default providers for each provider type. One of the providers connects to

SQL Server, and the other connects to Microsoft Access. As noted previously, the providers are

completely independent, even if they share a data store.


Choosing the right provider is therefore a matter of matching your needs with the capabilities of the data

store. For example, the AccessPersonalizationProvider connects to Microsoft Access, and is intended

for smaller sites in which the personalization data is fairly straightforward. Deployment is significantly

simplified when using AccessPersonalizationProvider, because Microsoft Access does not have the

same requirements as Microsoft SQL Server. The SqlPersonalizationProvider provides greater

flexibility and configurability, however, and is intended for scenarios where the scalability of an Access

database would be an issue.


A similar analysis can be made for the other provider types. Ultimately, if neither Access nor SQL Server

meet your data storage needs, you can create your own provider and plug it into the framework using the

Administration Website.


Developing Custom Providers


Creating a new provider is as easy as implementing a new class that meets the functional requirements

of the provider. Once the class has been developed, it can be registered using the Website Maintenance

Tool, thus enabling it as a provider of the correct type.
Custom provider solutions should be considered in cases where personalization data already exists, or

becomes too complex to manage using the default providers. If an application requires personalization

data that spans multiple datasources, such as user data in an LDAP directory and personal information in

a backend human resources repository, a custom provider could be used to interface with the

homogeneous data system.


Custom Membership Provider

Creating a custom membership provider involves several steps:


1.       Write a new class that derives from System.Web.Security.MembershipProvider.

2.       Use the Web Configuration Tool to register the provider. You can register the provider manually
     by adding a new <connectionStrings> element and a <membership> element.


3.         <configuration>

4.            <connectionStrings>

5.               <add name="MembershipProviderConnection"

6.                connectionString="DATA\mydb.mdb" />

7.            </connectionStrings>

8.            <system.web>

9.               <membership defaultProvider="FlatFileProvider">

10.                 <providers>

11.             <add
   connectionStringName="MembershipProviderConnection"

12.                            applicationName="/DoctorPortal"

13.                            description="Flat file membership provider"

14.                            requiresUniqueEmail="true"

15.                            enablePasswordRetrieval="false"

16.                            enablePasswordReset="true"

17.                            requiresQuestionAndAnswer="false"

18.                            passwordFormat="Hashed"

19.                            name="catdog"
20.                            type="MyCode.Membership.FlatFileProvider,

21.                                     MyCode.Membership,

22.                               Version=1.1.1300.0, Culture=neutral,

23.                               PublicKeyToken=xxxxxxxxxxxxxxxx" />

24.                           </providers>

25.                       </membership>

26.

27.         //other configuration pieces

28.                 </system.web>

      Note that whichever way you register the provider, you can declare whether the provider supports

      the various membership features such as automatic password retrieval or the actual password

      format.


29.       Make the datastore (database or other data source) available to the application.


Once the membership provider has been created, you can use your own data store to organize and

maintain users and roles.


Custom Profile Provider

Developing a custom profile provider requires a similar process, but the implementation class must

derive from the System.Web.Profile.ProfileProvider class. The ProfileProvider class is derived from

System.Configuration.SettingsProvider, which in turn inherits from

System.Configuration.Provider.ProviderBase. As a result, any custom profile provider must

implement all of the methods required by the ProfileProvider, SettingsProvider, and ProviderBase

abstract classes.


The personalization framework can then be configured to use the custom provider by adding a new entry

in the web.config file.


<profile defaultProvider="OdbcProvider">

      <providers>

          <add name="OdbcProvider"

           type="Samples.AspNet.Profile.OdbcProfileProvider"
                          connectionStringName="OdbcProfile" />

    </providers>

</profile>

The preceding code illustrates the profile section of the web.config file. A custom profile provider named

OdbcProvider is added to the provider list. The profile tag has its defaultProvider attribute set to the

OdbcProvider. The above configuration, along with a valid implementation of the ProfileProvider

class, is all that is required for a custom provider implementation.


Custom Personalization Provider

Creating a custom personalization provider also follows the same basic process, but a personalization

provider has to derive from System.Web.UI.WebControls.WebParts.PersonalizationProvider.

Once created, the provider can be registered automatically with the Web Configuration Tool, or manually

by adding an entry to the <providers> section of the <personalization> tag (which can be found

nested within the <webParts> element of the web.config file).


As with other custom providers, you are responsible for creating a valid data source and making it

available to the applications. Your personalization data source might be an XML file or entries in an Active

Directory. In either case, you'd have to define an appropriate schema for supporting personalization.


Conclusion

Personalizing a Website has always involved a large amount of complex supporting code. With the new

personalization features in ASP.NET 2.0, however, developers can not only create personalized

applications faster, they can also build entirely new classes of applications. The user management

system and login controls make recognizing a user even easier than before, and the profile features help

store user data in a fast and efficient manner. The Web Parts framework, however, provides a

revolutionary new design paradigm for Websites. Thanks to Web Parts, a Website is no longer

constrained to the linear document format that formed the basis for the HTML standard. Web Parts offer

much greater flexibility, and allow developers to create Web applications that are almost

indistinguishable from the most powerful desktop systems.


Related Books



        ASP.NET Unleashed

        A First Look at ASP.NET V. 2.0

        ASP.NET 2.0 Revealed
About the author


Jayesh Patel—Jay Patel is a developer in both .NET and Java Technologies. Jay's research focuses on

pattern-based programming and agile methodologies.


Bryan Acker—Bryan Acker is a technical writer for Infusion Development. Bryan has a strong

background in ASP and ASP.NET Web development and Web hosting.


Robert McGovern—Rob McGovern is a senior writer, developer, and project manager for Infusion

Development. Rob has worked on several different ASP.NET projects, including CodeNotes for ASP.NET

and the JSP to ASP.NET migration guide.


Infusion Development Corporation is a Microsoft-Certified Solutions Provider offering customized

software-development, training, and consulting services for Fortune 1000 Corporations, with an

emphasis on the financial-services industry. With offices in New York and Toronto, Infusion Development

has established an international client base, including some of the world's largest companies in the

financial service, securities brokerage, and software development industries. The employees of Infusion

Development are also the authors and creators of the CodeNotes book series.

				
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