1. Programming SharePoint Object Model, Web Services, and Events
Michael Morton
4/15/03

2. Summary of .NET support
SharePoint will use ASP.NET instead of ISAPI for base page execution
Web Part Framework
Server Object Model for programmatic access to SharePoint data
We offer functionality as XML web services for access from remote machines

3. .NET Object Model Managed code object model on the server
Accessible via ASP.NET or any other server process
Implemented in C#
Exposes almost of all of the data stored in WSS

4. NET Object model Examples of what can be done with the Object Mode:
Add, edit, delete, and retrieve data from SharePoint Lists
Create new lists and set list metadata (e.g. the fields in a list)
Set web properties
Work with documents in document libraries.
Perform administrative tasks such as creating webs, adding users, creating roles, etc.
Pretty much any functionality in the UI can be automated through the OM!

5. Example Objects Security Documents List Data SPGroup SPGroupCollection
SPSite
SPUser
SPUserCollection
Documents
SPDocumentLibrary
SPFile
SPFileCollection
SPFolder
List Data
SPField
SPFieldCollection
SPListCollection
SPList
SPListItemCollection
SPListItem
SPView
Administration
SPGlobalAdmin
SPQuota
SPVirtualServer

6. ASP.Net Security
For content stored in WSS, only registered set of web custom controls will run in pages
Inline script in the page will not execute
Code behind in pages can be made to work
All Executable code (e.g. web custom controls, web parts, and code-behind classes) needs to be installed on physical web server

7. Getting Started with OM
Build a web part
This is the best option to write code that functions are part of a WSS site or solution
There will be lots of documentation with the beta on how to build a web part.
Web Part is reusable and can be managed using all of the web part tools and UI.

8. Getting Started with the OM
Build an ASPX page
Code cannot live inline in a page within the site.
Creating pages underneath the /_layouts directory is often the best option for custom ASPX apps on top of SharePoint
This lets your page be accessible from any web. For example, if you build mypage.aspx in _Layouts, it is accessible from the following URLs:
ASPX page will run using the context of the web under which it is running.

9. Getting Started with the OM
Windows Executable or any other application
Object model can be called from pretty much any code context. It is not limited to just web parts or ASP.Net
For example, you could build a command-line utility to perform certain actions

10. Demo
Hello World Web Part

11. Working with the OM The object model has three top-level objects:
SPWeb (represents an individual site)
SPSite (represents a site collection, which is a set of web sites)
SPGlobalAdmin (used for global administration settings)
In order to perform actions on data within a web, you must first get an SPWeb object.

12. Adding our namespace
You should add references to the WSS namespaces to your source files
using Microsoft.SharePoint;
using Microsoft.SharePoint.WebControls;
using Microsoft.SharePoint.Administration; …

13. Key Object – SPWeb
Starting point to get at the Lists, Items, Documents, Users, Alerts, etc. for a web site.
Example Properties:
Web.Lists (returns a collection of lists)
Web.Title (returns the title of the site)
Web.Users (returns the users on the site)
In a web part or ASPX page, you can use the following line to get a SPWeb:
SPWeb myweb = SPControl.GetContextWeb(Context);

14. Demo
Showing Web and List Properties

15. Accessing data in a WSS List
Get a SPList or SPDocumentLibrary object.
SPList mylist = web.Lists[“Events”];
You can then call the .Items property to get all of the items:
SPListItemCollection items = mylist.Items;
If you only want a subset of the items, call the GetItems method and pass a SPQuery object
SPListItemCollection items = mylist.GetItems(query);

16. Accessing data in a list
To get data for a field, specify the field name in the indexer for an SPListItem
foreach(SPListItem item in items) {
Response.Write(item["Due Date"].ToString());
Response.Write(item["Status"].ToString());
Response.WRite(item["Title"].ToString()); }

17. Full Example SPWeb web = SPControl.GetContextWeb(Context);
SPList tasks = web.Lists["Tasks"];
SPListItemCollection items=tasks.Items;
foreach(SPListItem item in items) {
output.Write(item["Title"].ToString() + item["Status"].ToString() + "<br>"); }

18. Updating data
Most objects in WSS do not immediately update data when you change a property
You need to first call the Update() method on the object
This helps performance by minimizing SQL queries underneath the covers
Example:
SPList mylist = web.Lists[“Tasks”];
mylist.Title=“Tasks!!!”;
mylist.Description=“Description!!”;
Mylist.Update();

19. Updating List Data
SPListItem is another example of an object where you need to call update:
Example:
SPListItem item = items[0];
item["Status"]="Not Started";
item["Title"]="Task Title";
item.Update();

20. FormDigest Security
By default, the object model will not allow data updates if the form submitting the data does not contain the ‘FormDigest’ security key.
FormDigest is based on username and site. It will time out after 30 minutes.
Best solution is to include <FormDigest runat=“Server”/> web folder control in ASPX page.
If you do not need the security the FormDigest provides, you can set to SPWeb.AllowUnsafeUpdates to bypass this check.

21. Adding Users to a web Get the appropriate SPRole object:
SPRole admins = web.Roles["Administrator"];
Call the AddUser method:
Foltz","");

22. Demo
Adding users to the site via the OM

23. Keep objects around
If you create and destroy objects frequently, you may do extra SQL queries and have code that is incorrect:
Bad Example:
SPWeb web = SPControl.GetContextWeb(Context);
web.Lists["Tasks"].Title="mytitle";
web.Lists["Tasks"].Description="mydescription";
web.Lists["Tasks"].Update();
Good Example:
SPList mylist = web.Lists["Tasks"];
mylist.Title="mytitle";
mylist.Description="mydescription";
mylist.Update();

24. Web Services in WSS
SharePoint will have web services APIs for accessing content. The web services layer will be built on top of the server OM.
Allows manipulation of Lists, Webs, Views, List Items, etc.
Functionality will be similar to server object model, but with fewer interfaces optimized to minimize transactions.
Office11 (e.g. Excel, DataSheet, Work, Outlook, FrontPage, etc) use web services to access data from WSS.

25. Web Service Methods GetListCollection GetListItems GetWebCollection
UpdateList
UpdateListItems
GetWebInfo
GetWebPart
GetSmartPageDocument
And more…

26. Getting Started With Web Services
Create a Windows Application
In Visual Studio, choose ‘Add Web Reference’
Enter to access the lists web service
Other services include:
UserGroups.asmx – users and groups
Webs.asmx – Web information
Views.asmx – View information
Subscription.asmx – Subscriptions

27. Getting Started with Web Services
To send the logged on users’ credentials from the client, add the following line in the web reference object’s constructor:
public Lists() {
this.Url = "
this.Credentials=System.Net.CredentialCache.DefaultCredentials; }

28. Demo
Building a Web Service Client

29. Events We support events on document libraries.
Operations such as add, update, delete, check-in, check-out, etc.
Events are asynchronous
Events call IListEventSink managed interface.
Documentation and Sample in the SDK

30. Optimizing Performance of OM
The biggest goal is to minimize the number of SQL queries.
It may be helpful to use the SQL profiler to monitor what the OM is doing underneath the covers
Minimizing managed/unmanaged transitions also a goal, though this is mostly taken care within the OM.

31. What about CAML?
Page Execution will no longer be driven by CAML (XML schema used in SharePoint)
CAML is still used in several places
Field Type Definitions
Site and List Templates
View definitions

32. SDK Available
Documentation about V2 available at

33. Questions?

35. Code Example -- Enumerate Lists and Webs
private void ShowSubWebs(HtmlTextWriter output) {
SPWeb web = SPControl.GetContextWeb(Context);
SPWebCollection mywebs = web.Webs;
foreach (SPWeb myweb in mywebs)
output.Write(myweb.Title + "<br>"); }
private void ShowSubWebsWithLists(HtmlTextWriter output)
output.Write("<b>" + myweb.Title + "<br>" + "</b>");
SPListCollection lists = myweb.Lists;
foreach (SPList list in lists)
if (list.ItemCount>10)
output.Write(list.Title + ": " + list.ItemCount + "<br>");

36. Code Snippet – Copy Files
private SPWeb web;
private void Page_Load(object sender, System.EventArgs e) {
web = SPControl.GetContextWeb(Context); }
private void Button1_Click(object sender, System.EventArgs e)
int maxsize = Convert.ToInt32(TextBox1.Text);
SPFolder myfolder=web.GetFolder("Shared Documents");
SPFileCollection myfiles = myfolder.Files;
foreach (SPFile file in myfiles)
if (file.Length>(maxsize*1024))
Response.Write(file.Name + ": " + file.Length/ "kb<br>");
file.CopyTo("Archive/"+file.Name,true);

37. Code Snippet – Add users
private void Button1_Click(object sender, System.EventArgs e) {
SPWeb web = SPControl.GetContextWeb(Context);
string username = TextBox1.Text;
string displayname = TextBox2.Text;
string = TextBox3.Text;
SPRole admins = web.Roles["Administrator"];
try
admins.AddUser(username, ,displayname,"");
Label4.Text="Successfully added user"; }
catch(Exception ex)
Label4.Text=ex.ToString();