SharePoint 2010 hierarchy and related API classes

The structure of a SharePoint farm in most cases always is the same. First you have the SharePoint farm itself, in there you have one or more Web Applications, in a web application you have one or more site collections, in a site collection you have one or more sites, in a site you have one or more lists and in a list you have one or more list items.

Each of these levels has its own SharePoint API class. Instances of this class can be used to talk to these entities and do stuff with them.

When you start using these objects, it's important to dispose them when necessary. I lot of them implement the IDisposable interface, meaning you can use them in a so called 'using' statement. In the 'using' statement you create an instance of the class, do stuff with it and dispose of it when the 'using' statement comes to its end. This is important because a lot of these objects are quiet heavy and could cause a lot of memory usage or even memory leaks.

For example:

(using code example)

The respective classes

SPFarm - SharePoint farm

SPWebApplication - Web application

SPSite - Site collection

SPWeb - Site

SPList - List

SPListItem - Item

Some good things to know

Opening a web directly from the URL

   1: using (SPSite site = new SPSite("http://sitecollection1/subsite1"))

   2: {

   3:  

4: using (SPWeb web = site.OpenWeb())

   5:     {

   6:  

   7:         // Use the site/web object

   8:  

   9:     }

  10:  

  11: }

Using the ‘TryGetList’ method: new in SharePoint 2010 is the ‘TryGetList’ method to try to get a list in a given web. In the past, this could throw an exception and it was the only way to find out that the list did not exist.

   1: using (SPSite site = new SPSite("http://sitecollection1/subsite1"))

   2: {

   3:  

   4:     using (SPWeb web = site.OpenWeb())

   5:     {

   6:  

   7:         SPList list = web.Lists.TryGetList("ListTitle");

   8:  

   9:         if (list != null)

  10:         {

  11:  

  12:  

  13:             // List exist so you can safely use it

  14:  

  15:         }

  16:  

  17:     }

18:

  19: }

Finding particular list items: when you want to find list items based on their metadata, it’s not advisable to just write a for loop and check each item. It’s better to use a Collaborative Application Markup Language (CAML) query. A dedicated article in the ‘SharePoint for dummies’ series has been written for this.

   1: using (SPSite site = new SPSite("http://sitecollection1/subsite1"))

   2: {

   3:  

4: using (SPWeb web = site.OpenWeb())

   5:     {

   6:  

   7:         SPList list = web.Lists.TryGetList("ListTitle");

   8:  

   9:         if (list != null)

  10:         {

  11:  

  12:             SPQuery query = new SPQuery();

  13:             query.Query = "<Where>" +

14: "<Eq>" +

  15:                  "<FieldRef Name='Title' />" +

  16:                   "<Value Type='Text'>TitleYouWantToFind</Value>" +

  17:               "</Eq>" +

  18:             "</Where>";

  19:  

  20:             SPListItemCollection iColl = list.GetItems(query);

  21:  

  22:             // Loop the collection

  23:  

24: }

  25:  

  26:     }

  27:  

  28: }