SharePoint 2010 Object Model

Microsoft has replaced the "12 hive" structure that we had in SharePoint 2007 with "14 Hive" structure in 2010.

It has apparently added four new folders to its hive.

The Folders are :
* Policy
* UserCode
* WebClients
* WebServices

See the Details at : 14 hive Directory structure

In Sharepoint 2010 This is a step-by-step tutorial to learn using sharepoint 2010′s Server and client object model.
Server Object Model –

Here we will look at how to use SharePoint API’s, LINQ, REST and SharePoint web service to extract data from sharepoint server.

Lets Start with using the API’s in Microsoft.SharePoint and Microsoft.SharePoint.Utilities namespaces.

Firstly, to work with SharePoint 2010 components, your code must first establish the site context or site collection context for requests that are made to the server.

Please Note : In SharePoint, the SPsite object also refered to as Site is actually a “Site Collection” object, not a website
and the SPweb object also refered to as “web” is a single site in the site collection.(It can be a top-level site collection site).
also, object of type SPWebApplication is a big boss object which has reference to the web applictaion that contains the site collection.

To get the reference to site context in your code use the recommended Microsoft.SharePoint.SPContext class and its members.

Lets look at how it is used

To get a reference to the site collection -

SPSite oSiteCollection = SPContext.Current.Site;

To get a reference to the current web site or web in the site collection -

SPWeb oWebSite = SPContext.Current.Web;

or

SPWeb oWebSite = SPControl.GetContextWeb(Context);

Note : if your are using Microsoft.SharePoint.SPContext class, you should not dispose any SPSite or SPWeb object obtained
by any of the above methods. The SharePoint Foundation runtime will dispose of them after page completion.

To get a reference to all the webs or sites in a site collection -

SPWeb oWebSite = SPContext.Current.Site.AllWebs["mySite1"];

oWebSite.Dispose();

Note : You should explicitly dispose of references to objects that are obtained through the AllWebs() or Openweb() property. You can also use using clause
like below to avoid calling the dispose off method and let sharepoint do this for you.

using can be something like

using (SPWeb oWebSite = SPContext.Current.Site.AllWebs["mySite1"]);
{
…
}

You can also use the Openweb() as below

using (SPWeb oWebSite = mySiteCollection.OpenWeb(“mySite1″))
{
…
}

Lets look at some other components of the SharePoint farm that you can get using SPContext

To get a reference to the current top-level server farm object -

SPFarm myFarm = SPContext.Current.Site.WebApplication.Farm;

To get a reference to the site collection database -

SPSite oSiteCollection = SPContext.Current.Site.CurrentDatabase

Lets look at some of the general code snippets

To return the collection of site collections in a SharePoint Web application -

SPWebApplication webApplication = SPContext.Current.Site.WebApplication;

using (SPSiteCollection siteCollections = webApplication.Sites)
{

foreach (SPSite siteCollection in siteCollections)
{
Label1.Text += siteCollection.Url + “
”;

siteCollection.Close();
}

}

Note : To runthe above code reference the Microsoft.SharePoint.Administration.SPWebApplication assembly in your code.

To return the collection of The all the Webs or sites within a site collection, including the top-level site and all subsites.

SPSite oSiteCollection = SPContext.Current.Site;
using(SPWebCollection collWebsite = oSiteCollection.AllWebs);
{

for (int i = 0; i < collWebsite.Count; i++)
{
using (SPWeb oWebsite = collWebsite[i])
{
SPListCollection collList = oWebsite.Lists;

for (int j = 0; j < collList.Count; j++)
{
Label1.Text += SPEncode.HtmlEncode(collWebsite[i].Title) + ” ”
+ SPEncode.HtmlEncode(collList[j].Title) + “
”;
}
}}}

To return the all the subsites and lists of the current site

using (SPWeb oWebSite = mySiteCollection.OpenWeb())
{

using(SPWebCollection subSites = oWebsite.Webs)
{

foreach (SPWeb subSite in subSites)
{
Label1.Text += SPEncode.HtmlEncode(subSite.Title) + “
”;

SPListCollection collList = subSite.Lists;

foreach (SPList oList in collList)
{
Label1.Text += SPEncode.HtmlEncode(oList.Title) + ” ” +
oList.ItemCount.ToString() + “
”;

}subSite.Close();
}
}}