Microsoft SharePoint 2007 Technologies

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Featur es

In the previous chapter we discussed how to customize SharePoint using cus-

tom site definitions. Customizing SharePoint in this way is not new; Share-

Point Portal Server 2003 was built on the site definition and site template

infrastructure and included common XML files such as ONET.XML and

WebTemp.XML. However, comparing the content from the ONET.XML of

a SharePoint Portal Server 2003 site definition with the ONET.XML of a

SharePoint Server 2007 site definition shows a significant reduction in the

complexity and size of the ONET.XML. For example, one such difference is

the lack of content in the

ListTemplates element which, for SharePoint

2003, is responsible for defining the lists available to a site provisioned from

the site definition. The types of lists defined include an announcements list, a

document library, and a links list. Lists are still prevalent in SharePoint Server

2007 sites, so how do they get defined? The answer comes in the form of Fea-

tures. A Feature is a new concept introduced with the SharePoint Server

2007 platform which allows you to easily add and remove functionality and

customizations to and from your SharePoint sites. This chapter describes the

Feature architecture and steps you through the Feature lifecycle.

16.1 What is a Feature?

When it comes to customizing and extending the capabilities of a SharePoint

Portal Server 2003 deployment there is little in the way of efficiency or flexi-

bility. Outside of the Web Part world, adding new functionality, such as a

new type of list or navigation bar, to a SharePoint Portal Server 2003 deploy-

ment often results in creating a new custom site definition or modifying an

out-of-the-box site definition, thereby placing your deployment in unsup-

ported territory. It is cumbersome and inefficient to have to create an entire

custom site definition to implement additional functionality. Thankfully,

SharePoint Server 2007 introduces the concept of Features. A Feature is a

package of components that implements a specific piece of functionality to

your SharePoint deployment, such as a custom list, a set of Web Parts or a