ASP.NET Web Slices

Updated Wiki: Using ASP.NET Web Slices

davescriven — Sun, 19 Oct 2008 06:15:48 GMT

The recent Internet Explorer 8 Beta for Developers has brought us Activities and Web Slices. Web Slices already have a Firefox implementation. I'm hoping Activities will catch on and we'll see a Mozilla-based implementation soon (if there isn't one already) - the ability to load your own page within another is pretty cool.

The example we were shown at Remix was an Activity created to display car search results from any other page. E.g. I'm taking my regular look at the DBS and for a laugh I want to see how much they are. Instead of selecting the car name and pasting it into the browser search bar and looking through the results I simply select the car name, right-click and mouse-over the "Search in CarWebsite.." Activity and I see the search results in a mini-browser window!

For the moment though they're limited to IE8 - for now I'm gonna focus on web slices.

Web slices allow users to subscribe to specific content within a page, rather than the whole page (or site) like RSS. When clients detect a change in the content they can notify the user and display the updated slice in a small view pane in the browser.

I've just created a small ASP.NET Web Slices project over at Codeplex that contains, among other things, a WebSlice ASP.NET control. Using this control it's a simple job of creating a new web application with web slices and also easy to add web slices to an existing application. The control works much like an <asp:Panel/> control in that it's a container for other controls. Any child controls of this WebSlice will be the web slice content. The Title, TimeToLive and EndTime control properties can be used to further customise the web slices.

<body>
     <form id="form1" runat="server">
         <div>
             <slices:WebSlice Title="Web Slice Title" runat="server" ID="slice" EndTime="06/06/2008" TimeToLive="1:00:00">
                 <p>Lorem...</p>
                 <p>Expires on <asp:PlaceHolder ID="endTime" runat="server" /> 
                 (Updates every <asp:PlaceHolder runat="server" ID="timeToLive" /> minutes)</p>
             </slices:WebSlice>
         </div>
     </form>
</body>

The output is simple XHTML with the required web slice CSS classes.

<div id="Div1" class="hslice">
     <h4 class="entry-title">Web Slice Title</h4>
     <div class="entry-content">
         <p>Lorem...</p>
         <p>Expires on <abbr class="end-time" title="2008-06-06T00:00:00">Fri, 06 Jun 2008 00:00:00 GMT</abbr> (Updates every <span class="ttl">60</span> minutes)</p>
     </div>
</div>

There isn't any magic going on here. The control is simply taking care of markup and semantics instead of copy-paste work. When IE 8 parses the above XHTML it will know that this is a web slice and will allow the user to subscribe to it:

WebSliceSubscribe

There are also some extension methods available on Page objects when the WebSlices namespaces is being used. These methods allow the developer to customise the discovery of web slices.

At the moment there are two methods. The first is named SetDefaultWebSlice<TWebSlice>(TWebSlice slice) and provides a means to set the default web slice. You'd pretty much only do this when there are several slices on the page and the one you want to be default appears after other slices (the first slice to be parsed is the default).

using WebSlices;
  
namespace SampleApplication
{
     public partial class _Default : System.Web.UI.Page
     {
         protected void Page_Load(object sender, EventArgs e)
         {
             this.SetDefaultWebSlice<WebSlice>(this.slice);
         }
     }
 }

The second method is named SetWebSliceDiscoveryMode(WebSliceDiscoveryMode mode) and allows developers to turn off web slice discovery for the current page.

using WebSlices;
  
namespace SampleApplication
{
     public partial class _Default : System.Web.UI.Page
     {
         protected void Page_Load(object sender, EventArgs e)
         {
             this.SetWebSliceDiscoveryMode(WebSliceDiscoveryMode.Off);
         }
     }
}

ASP.NET Web Slices using web slices easy and allows developers with little or no inclination to start writing (read: copy and pasting) XHTML around to use web slices in their application. It's certainly not complete and there is more to do - better customisation and a JavaScript library to be able to add and update the slices in the browser are up next.

Perhaps web slices will never take off. If they don't I'm sure there will be more features in the future based off the idea. I certainly see them being useful for small web sites that have no CMS to generate RSS feeds automatically. With web slices the HTML and browser do this work for them - all they need do is modify their markup and users can be notified of changes. Ebay have also put the feature to good use in their IE8 specific implementation. I'm looking forward to seeing how other sites implement the new features.

Updated Wiki: Home

davescriven — Sun, 19 Oct 2008 06:08:38 GMT

ASP.NET Web Slices is a framework for creating web slice enabled ASP.NET applications.

Web slices allow users to subscribe to specific content within a page, rather than the whole page (or site) like RSS. When clients detect a change in the content they can notify the user and display the updated slice in a small view pane in the browser.

The WebSlice control is used like an <asp:Panel/> control to wrap the contents of the web slice. The WebSlice control rendered output contains the necessary HTML and CSS classes to be recognised as a Web Slice.

Using ASP.NET Web Slices

When the WebSlices namespace is imported several extension methods are added to the System.Web.UI.Page class:

SetDefaultWebSlice<TWebSlice>(TWebSlice slice) - this method allows developers to specify the default web slice if there are many on a single page.
SetWebSliceDiscoveryMode(WebSliceDiscoveryMode mode) - this method allows developers to disable (or enable) web slice discovery for a page.

UPDATED RELEASE: WebSlices 1.0 (Jun 04, 2008)

Wed, 04 Jun 2008 13:09:50 GMT

This release contains a WebSlice server control as well as several Page extension methods.

CREATED RELEASE: WebSlices 1.0 (Jun 04, 2008)

Wed, 04 Jun 2008 13:07:27 GMT

This release contains a WebSlice server control as well as several Page extension methods.

Source code checked in

davescriven — Sun, 01 Jun 2008 01:22:26 GMT

- Changed the behaviour of EndTime and TimeToLive : No longer render at the bottom of the web slice content. Instead, container controls are required inside the control tree. E.g. If EndTime is specified the developer will have to add a place holder control inside the web slice content: <p>Expires on <asp:PlaceHolder ID="endTime" runat="server"/>.</p> This allows far greater customisation of the display of EndTime and TimeToLive (who's container ID is "timeToLive"). The EndTimePlaceHolderId and TimeToLivePlaceholderId properties default to "endTime" and "timeToLive" but can be set to different values. Note that PlaceHolder controls are not required - any control can be used but these controls provide no extra markup. - Now a CompositeControl to allow searching for the required EndTime and TimeToLive place holders within the slice.

UPDATED WIKI: Home

davescriven — Sun, 01 Jun 2008 00:22:45 GMT

ASP.NET Web Slices is a framework for creating web slice enabled ASP.NET applications.

Web slices allow users to subscribe to specific content within a page, rather than the whole page (or site) like RSS. When clients detect a change in the content they can notify the user and display the updated slice in a small view pane in the browser.

The WebSlice control is used like an <asp:Panel/> control to wrap the contents of the web slice. The WebSlice control rendered output contains the necessary HTML and CSS classes to be recognised as a Web Slice.

Read about how to use ASP.NET Web Slices.

When the WebSlices namespace is imported several extension methods are added to the System.Web.UI.Page class:

SetDefaultWebSlice<TWebSlice>(TWebSlice slice) - this method allows developers to specify the default web slice if there are many on a single page.
SetWebSliceDiscoveryMode(WebSliceDiscoveryMode mode) - this method allows developers to disable (or enable) web slice discovery for a page.

UPDATED WIKI: Home

davescriven — Sat, 31 May 2008 14:23:49 GMT

Project Description
ASP.NET Web Slices is a framework for creating web slice enabled ASP.NET applications.

Web slices allow users to subscribe to specific content within a page, rather than the whole page (or site) like RSS. When clients detect a change in the content they can notify the user and display the updated slice in a small view pane in the browser.

The WebSlice control is used like an <asp:Panel/> control to wrap the contents of the web slice. The WebSlice control rendered output contains the necessary HTML and CSS classes to be recognised as a Web Slice.

Read about how to use ASP.NET Web Slices.

When the WebSlices namespace is imported several extension methods are added to the System.Web.UI.Page class:

SetDefaultWebSlice<TWebSlice>(TWebSlice slice) - this method allows developers to specify the default web slice if there are many on a single page.
SetWebSliceDiscoveryMode(WebSliceDiscoveryMode mode) - this method allows developers to disable (or enable) web slice discovery for a page.

Source code checked in

davescriven — Sat, 31 May 2008 14:11:43 GMT

Added basic designer support for the WebSlice control (controls can be dropped in and a semi-transparent web slice icon appears in the top right of the control).

UPDATED WIKI: Home

davescriven — Sat, 31 May 2008 13:19:35 GMT

Project Description
ASP.NET Web Slices is a framework for creating web slice enabled ASP.NET applications.

The WebSlice control is used like an <asp:Panel/> control to wrap the contents of the web slice. The WebSlice control rendered output contains the necessary HTML and CSS classes to be recognised as a Web Slice.

Read about how to use ASP.NET Web Slices.

When the WebSlices namespace is imported several extension methods are added to the System.Web.UI.Page class:

SetDefaultWebSlice<TWebSlice>(TWebSlice slice) - this method allows developers to specify the default web slice if there are many on a single page.
SetWebSliceDiscoveryMode(WebSliceDiscoveryMode mode) - this method allows developers to disable (or enable) web slice discovery for a page.

UPDATED WIKI: Home

davescriven — Sat, 31 May 2008 13:19:06 GMT

Project Description
ASP.NET Web Slices is a framework for creating web slice enabled ASP.NET applications.

The WebSlice control is used like an <asp:Panel/> control to wrap the contents of the web slice. The WebSlice control rendered output contains the necessary HTML and CSS classes to be recognised as a Web Slice.

http://furious-angel.net/post/2008/05/ASPNET-Web-Slices.aspx.

When the WebSlices namespace is imported several extension methods are added to the System.Web.UI.Page class:

SetDefaultWebSlice<TWebSlice>(TWebSlice slice) - this method allows developers to specify the default web slice if there are many on a single page.
SetWebSliceDiscoveryMode(WebSliceDiscoveryMode mode) - this method allows developers to disable (or enable) web slice discovery for a page.

Source code checked in

davescriven — Sat, 31 May 2008 13:07:35 GMT

Added support for EndTime and TimeToLive, although the text displayed should be customisable in future.

UPDATED WIKI: Home

davescriven — Sat, 31 May 2008 07:25:32 GMT

Project Description
ASP.NET Web Slices is a framework for creating web slice enabled ASP.NET applications.

The WebSlice control is used like an <asp:Panel/> control to wrap the contents of the web slice. The WebSlice control rendered output contains the necessary HTML and CSS classes to be recognised as a Web Slice.

When the WebSlices namespace is imported several extension methods are added to the System.Web.UI.Page class:

SetDefaultWebSlice<TWebSlice>(TWebSlice slice) - this method allows developers to specify the default web slice if there are many on a single page.
SetWebSliceDiscoveryMode(WebSliceDiscoveryMode mode) - this method allows developers to disable (or enable) web slice discovery for a page.

UPDATED WIKI: Home

davescriven — Sat, 31 May 2008 07:24:48 GMT

Project Description
ASP.NET Web Slices is a framework for creating web slice enabled ASP.NET applications.

The WebSlice control is used like an <asp:Panel/> control to wrap the contents of the web slice. The WebSlice control rendered output contains the necessary HTML and CSS classes to be recognised as a Web Slice.

When the WebSlices namespace is imported several extension methods are added to the System.Web.UI.Page class:

SetDefaultWebSlice<TWebSlice>(TWebSlice slice) - this method allows developers to specify the default web slice if there are many on a single page.
SetWebSliceDiscoveryMode(WebSliceDiscoveryMode mode) - this method allows developers to disable (or enable) web slice discovery for a page.

UPDATED WIKI: Home

davescriven — Sat, 31 May 2008 07:24:25 GMT

SetDefaultWebSlice<TWebSlice>(TWebSlice slice) - this method allows developers to specify the default web slice if there are many on a single page.

SetWebSliceDiscoveryMode(WebSliceDiscoveryMode mode) - this method allows developers to disable (or enable) web slice discovery for a page.

Source code checked in

davescriven — Sat, 31 May 2008 06:53:10 GMT

Ensured that ClientID is used to reference the web slices.

Source code checked in

davescriven — Sat, 31 May 2008 06:48:16 GMT

The initial upload of the web slices framework source code - this contains a WebSlice server control and a WebSliceHelper class with extension methods.

UPDATED WIKI: Home

davescriven — Sat, 31 May 2008 06:04:36 GMT

Project Description
ASP.NET Web Slices is a framework for creating web slice enabled ASP.NET applications.