Tag / SharePoint 2010

by Simon Doy

Introducing SPUrlExpressionBuilder to resolve SharePoint URL Tokens


Introduction

One of the great things when developing with SharePoint is being able to use URL tokens such as:-

  • ~SiteCollection – this will resolve to the current site collection root
  • ~Site – this will resolve to the current web root

For an extensive list of SharePoint URL tokens, take a look at Namwar Rizvi’s SharePoint Insight blog post, http://sharepoint-insight.com/2008/12/01/list-of-sharepoint-url-tokens/.

If you have done much with creating or modifying Master Pages or Page Layouts then these tokens become very useful to locate resources such as images, XSL or CSS files.

For example, to reference an image which is stored in a SharePoint Publishing web’s Site Collection Images folder you could use something like this:-

~SiteCollection/SiteCollectionImages/myimage.png.

Recently, I have been working with multiple language user interfaces and wanted to be able to display a different image based on the language. One of the steps to do this was to work out how to process these URL Tokens.

Solution

This is where the SPUrlExpressionBuilder class comes to the rescue. This class is part of the Microsoft.SharePoint.Publishing.WebControls assembly.

To evaluate a string with a url token like ~SiteCollectionUrl/Images/MyImage.png you can use the following SPUrlExpressionBuilder class’s method EvaluateUrlExpression().

string imagePath = SPUrlExpressionBuilder.EvaluateUrlExpression("~SiteCollection/Images/myimage.png").ToString();

 

by Simon Doy

SharePoint Feature Receiver token replacement only works with Guids using lower case characters


Introduction

This week I have been writing my first proper SharePoint 2010 Service Application.

Part of that solution is using a Feature Receiver to install the various components that make up a Service Application. These include:-

  • Service
  • Service Proxy
  • Service Application
  • Service Application Proxy
  • Service Instance

Tip: Andrew Connell’s chapter in the Real World SharePoint 2010 book is an excellent resource for getting the plumbing of the service application setup.

One of the issues came about at deployment time. Now that I write this, I do remember hearing about this issue before when during a SharePoint 2010 Developer Bootcamp. Of course I didn’t take enough notice and then hit the problem when I decided to update the GUID for the feature receiver.

The following error was displayed when deploying the solution:-

Error occurred in deployment step ‘Add Solution’: Failed to create receiver object from assembly “ITSP.SPMonitoringStatusPackage, Version=1.0.0.0, Culture=neutral, PublicKeyToken=de085cbd57463aa2”, class “$SharePoint.Type.edd0669b-2393-4fe6-988d-17a2De06c6e4.FullName$” for feature “ITSP.SPMonitoringStatusPackage_ITSP.SPMonitoringStatusInstaller” (ID: a5ede1b3-cbd6-4918-9f31-4322603295f5).: System.ArgumentNullException: Value cannot be null.
Parameter name: type
at System.Activator.CreateInstance(Type type, Boolean nonPublic)
at Microsoft.SharePoint.Administration.SPFeatureDefinition.get_ReceiverObject()

Screenshot:-

guid-featurereceiverdeployerror

The deployment show that any error occured because it could not create a feature receiver object from assembly “ITSP.SPMonitoringStatusPackage, Version=1.0.0.0, Culture=neutral, PublicKeyToken=de085cbd57463aa2” with the class “$SharePoint.Type.{GUID}.FullName$”.

The token, “$SharePoint.Type.{GUID}.FullName$”, should be replaced by Visual Studio as part of the build process. However this does not seem to happen with the GUID value that I was using (see below).

In this example the {GUID} value is specified against the feature receiver class using an attribute as below (please note the capital letters have been added for this example):-

guid-featurereceiveruppercase

The item that uses this GUID attribute for the Feature Receiver Class can be seen by double-clicking on the feature Visual Studio SPI object:-

featureceiver-spi

If you then look at the properties of the feature Visual Studio SPI object, you see the section as below:-

featureceiver-spi-properties

As you can see the Receiver Class has a value of:-

$SharePoint.Type.edd0669b-2393-4fe6-988d-17a2De06c6e4.FullName$

 

Solution

The issue is that upper case characters are being used and changing these to use lower case alphabetic characters for the GUID fixes the issue.

The following changes need to be made.

  1. Change the Feature Receiver’s GUID attribute.
 1: [Guid("edd0669b-2393-4fe6-988d-17a2de06c6e4")]

 

 2:     public class ITSPSPMonitoringStatusInstallerFeatureReceiver : SPFeatureReceiver

 

2. Update the Feature Receiver Visual Studio SPI object’s Receiver Class property to:-

featureceiver-spi-properties-fixed

Save all the files, rebuild, deploy and the solution is deployed successfully, hurrah!

feature-installed-successfully

 

Hope that helps.