Microsoft .NET Magazine #17: Legends never die on the front ?!

Today I spotted myself on the cover of the new Microsoft .NET Magazine....



I will post some more info when I have got the time for it....
Notice that JOPX has a nice cool earring.... ;)

Microsoft .NET Magazine:
http://www.microsoft.com/netherlands/msdn/netmagazine/default.aspx

Creating Managed Properties for use in SharePoint Server Enterprise Custom Search through Code

Use the following Code to add Managed Properties in Code, the Managed Properties are created from crawled properties (like an infopath published form)

//Get search Schema
ServerContext serverContext = ServerContext.GetContext("SharedServices1");
SearchContext searchContext = SearchContext.GetContext(serverContext);  
Schema schema = new Schema(searchContext);

//Get the list of properties (here from a published infoPath Form), you want to use in search
StringCollection infoPathFormProperties = GetData.GetAllInfoPathPublishedFields();
// Create new ManagedProperties
foreach (string infoPathFormProperty in infoPathFormProperties)
{ 
        string managedPropertyName = infoPathFormProperty;
        string infoPathFormPropertyPublished = string.Format("ows_{0}", infoPathFormProperty); //infopath published fields will be added as ows_[NAME]

        // If you create a prop that already exists, you will get an SqlException (duplicate key),so you need this check
        if (!schema.AllManagedProperties.Contains(managedPropertyName))
        {                
             ManagedProperty newManagedProperty = schema.AllManagedProperties.Create(managedPropertyName, ManagedDataType.Text);

             // Get the (crawled) property you want to map in the ManagedProperty
             CrawledProperty cprop = null;
             foreach (CrawledProperty prop in schema.QueryCrawledProperties(infoPathFormPropertyPublished, 1000, Guid.NewGuid(), string.Empty, true))
             {
                  //schema.GetCrawledProperty(Guid.NewGuid(), infoPathFormPropertyPublished, 0); //can't use this, you need also need the Guid and variantType, and you only know the name
                  //QueryCrawledProperties will be filtered on CONTAINING infoPathFormPropertyPublished value, so extra check if the Name is equal!
                  if (prop.Name == infoPathFormPropertyPublished)
                  { 
                       cprop = prop;
                       break;
                  }
              }

              if (cprop != null)
              {
                   // Map the crawled prop to the Managed Prop
                   MappingCollection mappings = new MappingCollection();
                   mappings.Add(new Mapping(cprop.Propset, cprop.Name, cprop.VariantType, newManagedProperty.PID));

                   newManagedProperty.SetMappings(mappings);

                   // Set Some other properties
                   newManagedProperty.FullTextQueriable = true;
                   newManagedProperty.EnabledForScoping = true;
                   newManagedProperty.Update();
               }
               else 
               {
                   MessageBox.Show(string.Format("Published Infopath field {0} not found",infoPathFormPropertyPublished));    
               }

               }
        else
        {
             MessageBox.Show(infoPathFormProperty  +" already exists");
        }            
}          

SOURCES:

• Blogpost from Patrick Tisseghem on MSDN:
  Creating and Exposing Managed Properties in the Advanced Search Page of SharePoint Server Enterprise Search (technical details)
• Managing Metadata : explaining the functional details

Some late Christmas gifts for Sharepoint Developers!

Thx to JOPX he made a post with some very usefull links for Sharepoint Developers, check out his blog for more tips, tricks, tools and fools ;-)

DEBUGGING TIPS:

• Script to recycle specific Application pool (instead of slow iisreset):
  App Pool Recycler for SharePoint devs
• Debugger "Feature" for SharePoint
  

CAML QUERY

• SPCamlViewer Tool by Renaud Comte (very good tool to test caml)
• CAML Query Builder (creating dynamic, reusable CAML query components)
  check out some examples here

QUERY SHAREPOINT

• MOSS Query Tool
  
  

SPSecurity.RunWithElevatedPrivileges to update SPRoleAssignment of an SPListItem

When you write custom code in Sharepoint webparts, your code will run with your credentials.
Not everybody has Full Control, so when a user has only read rights, the code will throw an access denied error when the code needs access to objects that are not in the scope of the user credentials.... (example: add the username in the ReadBy properties of an item).

What you need is impersonation, run your code with the help of a user who has just enough rights to run it. Sharepoint has a built-in function to accomplish this: SPSecurity.RunWithElevatedPrivileges, it runs with the System Account User.

Some things you should know when using SPSecurity.RunWithElevatedPrivileges:

• in the delegate function, you must build a new SPSite/SPWeb object (like SPSite siteColl = new SPSite(App.SITE_COLLECTION_URL)) and you can't use the SPContext.Current.Web, because the SPContext runs with the current context (with current user).
• Also set the AllowUnsafeUpdates property of the site/web where you will be updating/accessing stuff to true, to be sure you don't get an error like "The security validation for this page is invalid" (see more below). If you don't do it, you code will work, but when returning from the delegate function, the error will arise..

Code sample:

I run the "Elevated code" when the button btn is clicked in a webpart:

void btn_Click(object sender, EventArgs e)
{
   {
     SPSecurity.RunWithElevatedPrivileges(TestSec);
   }
   catch (Exception ex)
   {
     throw ex;
   }
}

public void TestSec()
  {
    SPSite siteColl = new SPSite(App.SITE_COLLECTION_URL);
    SPWeb site = siteColl.AllWebs[App.WEB_NAME];
    SPList list = site.Lists["Test"];

    SPListItem testItem = list.GetItemById(1);
    site.AllowUnsafeUpdates = true;
    SPRoleDefinition roleDefinitionContributor = site.RoleDefinitions.GetByType(SPRoleType.Contributor);
    SPRoleAssignment roleAssignment = new SPRoleAssignment("DOMAIN\\USERNAME", "", "", "");
    roleAssignment.RoleDefinitionBindings.Add(roleDefinitionContributor);
    ////Check for permission inheritance, and break if necessary
    if (!testItem.HasUniqueRoleAssignments)
    {
      testItem.BreakRoleInheritance(false); //pass true to copy role assignments from parent, false to start from scratch
    }
  testItem.RoleAssignments.Add(roleAssignment);
  testItem.Update();
  site.AllowUnsafeUpdates = false;
  siteColl.Close();
  site.Close();

}

Error when not setting AllowUnsafeUpdates = true:

Server Error in '/' Application.
--------------------------------------------------------------------------------
The security validation for this page is invalid. Click Back in your Web browser, refresh the page, and try your operation again.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Runtime.InteropServices.COMException: The security validation for this page is invalid. Click Back in your Web browser, refresh the page, and try your operation again.
Source Error:
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.
Stack Trace:

[COMException (0x8102006d): The security validation for this page is invalid. Click Back in your Web browser, refresh the page, and try your operation again.]
Microsoft.SharePoint.Library.SPRequestInternalClass.UpdateRoleAssignment(String bstrUrl, Guid& pguidScopeId, Int32 lPrincipalID, Object& pvarArrIdRolesToAdd, Object& pvarArrIdRolesToRemove) +0
Microsoft.SharePoint.Library.SPRequest.UpdateRoleAssignment(String bstrUrl, Guid& pguidScopeId, Int32 lPrincipalID, Object& pvarArrIdRolesToAdd, Object& pvarArrIdRolesToRemove) +119
[SPException: The security validation for this page is invalid. Click Back in your Web browser, refresh the page, and try your operation again.]
OfficialMail.WebParts.TestWebPart.btn_Click(Object sender, EventArgs e) +94
System.Web.UI.WebControls.Button.OnClick(EventArgs e) +105
System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +107
System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +7
System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +11
System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +33
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +5102

Sources:

• http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=1499458&SiteID=1
• http://daniellarson.spaces.live.com/?_c11_BlogPart_FullView=1&_c11_BlogPart_BlogPart=blogview&_c=BlogPart&partqs=amonth%3D1%26ayear%3D2007

Invalid characters and URLs in SharePoint 2007 (2003)

Nice to know when developping Sharepoint stuff:

Invalid characters and URLs in SharePoint (Eric Legault My Eggo blog)

Thx to Jopx for the link

Reflector 5

Handy tool:

Download it here:

• Reflector 5.0
• Reflector 5.0 Add-Ins @ CodePlex
• Reflector 5.0 New Features (PPT)

More info @ http://www.hanselman.com/blog/Reflector5ReleasedWorldDominationAssured.aspx

Working with the Replicator in Sharepoint Workflows, some serialize issues & tricks

Before reading this post:

• Read about workflows and its replicator activity.
• ECM Starter Kit and Workflow Development Starter Kit for WSS 3.0 RTM: many examples

Keep in mind: A replicator is just a "workflow foreach".


When initializing a replicator you need to pass initiation data (like the foreach collection data). So if you want to pass a Contact for each replicated activity, you will set the initiationChildData (must implement IList) with Contact objects:
adding contacts like this: replicatorInitialChildData.Add(contact);

Sometimes you want the add your own classes to the List. You would except that this wouldn't be difficult, in fact it isn't:

Create the initiation data list with objects of your custom class:
IList replicatorInitialChildData = new List();
/ fill the list with the ApproverFlow objects
replicatorInitialChildData.Add(appFlowObj1);
replicatorInitialChildData.Add(appFlowObj2);

The code will compile, the workflow will succeed sometimes (when the replicator is used in Parallel execution), sometimes not (when the replicator is used in Sequence execution), after a while you will notice this kind of errors:

(in the log folder in C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\LOGS)

Workflow Infrastructure 72eo Unexpected DehydrateInstance: System.Runtime.Serialization.SerializationException: End of
Stream encountered before parsing was completed. at System.Runtime.Serialization.Formatters.Binary.__BinaryParser.Run() at
System.Runtime.Serialization.Formatters.Binary.ObjectReader.Deserialize(HeaderHandler handler, __BinaryParser serParser, Boolean fCheck,
Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage) at
System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream serializationStream, HeaderHandler handler, Boolean
fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage) at
System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream serializationStream) at
System.Workflow.ComponentModel.Activity.Load(Stream stream,...

02/27/2007 14:50:31.00* w3wp.exe (0x0A98) 0x1700 Windows SharePoint Services Workflow Infrastructure
72eo Unexpected ... Activity outerActivity, IFormatter formatter) at
System.Workflow.ComponentModel.Activity.Load(Stream stream, Activity outerActivity) at
System.Workflow.Runtime.Hosting.WorkflowPersistenceService.RestoreFromDefaultSerializedForm(Byte[] activityBytes, Activity outerActivity)
at Microsoft.SharePoint.Workflow.SPWinOePersistenceService.LoadWorkflowInstanceState(Guid instanceId) at
System.Workflow.Runtime.WorkflowRuntime.InitializeExecutor(Guid instanceId, CreationContext context, WorkflowExecutor executor,
WorkflowInstance workflowInstance) at System.Workflow.Runtime.WorkflowRuntime.Load(Guid key, CreationContext context,
WorkflowInstance workflowInstance) at System.Workflow.Runtime.WorkflowRuntime.GetWorkflow(Guid instanceId) at
Microsoft.SharePoint.Workflow.SPWinO...

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. --->
System.InvalidOperationException: The platform does not know how to deserialize an object of type OfficialMail.Common.ApproverFlow+Approver. The platform can deserialize primitive types such as strings, integers, and GUIDs; other
SPPersistedObjects or SPAutoserializingObjects; or collections of any of the above. Consider redesigning your objects to store values in
one of these supported formats, or contact your software vendor for support.


You will notice the deserialize stuff.... If you think further, ..... whole the workflow idea is that every instance can be serialized or deserialized, because a workflow can wait for some other stuff, so objects will be saved somewhere (not in memory) when workflow is waiting.

When the replicator starts in parallel execution, no (de)serialize will occur because the workflow doens't need to serialize the objects, the replicator executes everything at once.
But when the replicator executes in sequence, it does need (de)serializing because the workflow will pause before executing the next step (so state is saved:(de)serializing occurs).


So when you want to add your own classes, keep in mind that your own class must be serializable.

Which types are serializable?
The platform can deserialize primitive types such as strings, integers, and GUIDs; other SPPersistedObjects or SPAutoserializingObjects; or collections of any of the above.

In one of the next blog posts, I will explain how to add/change data when the replicator is already running ...

Team System : Team Explorer free download!

A reminder for myself ;-)

An essential client-side piece of Team System that installs as a Visual Studio 2005 add-in:
http://blogs.vertigosoftware.com/teamsystem/archive/2006/05/22/2778.aspx

All good things come to an end, Bye Bye Janka: 08/06/95 - 14/02/07 - FOREVER

In My Memory.......

Handle the InfoPath Forms Services by yourself (in a Custom WebPart to view a web-enabled Infopath 2007 Form)

To understand this post well, please go through this post first:
- Hosting the InfoPath 2007 Form Editing Environment in a Custom Web Form

Sometimes you don't want to popup an error by InfoPath Forms Services (it will log this also in the EventLog), see image below. You want to catch the error in code and do some custom logging (or other stuff)

I will use the example when a dataconnection (webservices) in the form gives a time-out.

Preceding:
First keep in mind that we will bind the dataconnection-webservice to its control in code, so you have to deselect - Automatically retrieve data when form is opened (when adding a data-connection in InfoPath). Also don't forget to link the control with the dataconnection in infopath designer

What we gonna do in code:
- Add a handler that will get you into the Initialize methods of the XmlFormView
- Get the right dataconnection, execute it (so it will get the data and bind to the control)
- Add a "try/catch" block around this code

The code:

void viewform_Initialize(object sender, InitializeEventArgs e)
{
   try
   {
      DataConnection dc = _viewform.XmlForm.DataSources["GetGAL"].QueryConnection;
      dc.Execute();
   }
   catch (System.Net.WebException webEx)
   {
      WarmUpWebService();
      ReloadWebPart();
      //Log, ...
   }
   catch (Exception ex)
   {     
      Logger.Log(ex, ...);
   }
}


Some other InfoPath blogs:
InfoPath Developer Portal 
Designing Form Templates With The New Features Of InfoPath 
InfoPath BLOG Site 

Time-outs when using WebEnabled Infopath Form in Sharepoint 2007 WebParts

When you are using web-enabled infopath forms (that have dataconnections to webservices) in sharepoint 2007, you can get timeouts errors....

Example of an Time-out Exception:
Forms Services Runtime - Data Connections - TYPE: WARNING - EVENT 5566
The following query failed: GetSomething (User: MMMM\bbbbb, Form Name: formname, IP: , Request: http://serverZZZ/xxxx/yyyyy/composer.aspx?menu=3&Type=0, Form ID: urn:schemas-microsoft-com:office:infopath:xxxxxxx:-myXSD-2006-08-07T07-37-16, Type: DataAdapterException, Exception Message: The operation has timed outThe operation has timed out)

How to solve them?

1. Check if your WebServices time-outs occur when you use the WebService directly (in a webbrowers), If so, you should change the timeout of the WebService in IIS Manager (InetMgr) or use more caching.
   
   
2. If you are loading the Web-enabled InfoPath form into a custom webpart, you have to be sure that the following setting is used in the Form Library Advanced Settings page:
   Display as a Web Page (in stead of Open in the client application)
   
   


3. Change the Data Connection Timeouts Settings. Open SharePoint 3.0 Central Administration: Goto Application Management > Configure InfoPath Forms Services
   Here you can change the Data Connection Timeouts Settings
   
   

Point 2 has fixed my problems...

Problems starting VSTA in Infopath 2007 with Microsoft Office Server Sharepoint 2007 (.NET 3.0) installed *!!!FIXED!!!*

To fix the problem described below:

It worked for me when I did this:
uninstall .NET programmability support for .NET Framework version 2.0 and then reinstall it

(go to Kristof his blog for full explanation)

When I want to add custom C# in an Infopath 2007 form, I get this error:

InfoPath cannot start Microsoft Visual Studio Tools for Applications.
To work with Visual Basic or C# code, Microsoft Visual Studio Tools for Applications (VSTA) is required. the Microsoft .NET Framework 2.0 and Microsoft Core XML Services 6.0 must be installed prior to installing VSTA. To install VSTA, open Add or Remove Programs, locate your 2007 Microsoft Office System installation, and then click Change

How should I make this work? Reinstalling some things? I think the .NET 3.0 will cause the problems....

This stuff is installed:

• Microsoft .NET Compact Framework 1.0 SP3 Developer
• Microsoft .NET Compact Framework 2.0
• Microsoft .NET Framework 2.0
• Microsoft .NET Framework 3.0
• Microsoft Office Enterprise 2007
• Microsoft Office Sharepoint Designer 2007
• Microsoft Office Sharepoint Server 2007
• Microsoft Visual Studio 2005 Professional Edition
• Microsoft Visual Studio 2005 Team Explorer
• Microsoft Visual Studio 2005 Tools for Office Runtime
• Windows Server 2003 Service Pack 1
• Regarding Workflow:
  Enterprise Content Management Starter Kit for 2007 Office System (beta 2 tr)

When I want to re-installing MSXML 6.0 I get this error:

Installation of MSXML 6.0 Parser failed because a higher version already exists on the machine. To proceed uninstall the higher version and then run MSXML 6.0 Parser Setup again

Kristof De Causemaeker add some more comments:
When you want to create an InfoPath Add-in project via VSTO, it also give errors...
I thinks that VSTO/VSTA in combination with .NET 3.0 and InfoPath 2007 will not work yet..... Maybe a Windows Registry problem?

Developing Workflow in VS for Sharepoint 2007

!MUST READ! Developing Workflows Tutorials on http://blogs.msdn.com/sharepoint/:
Developing Workflows in VS: Part 1 - Workflow Objects and A Crash Course on Mechanics
Developing Workflows in VS: Part 2 - Planning Your Workflow: Two Things to Keep in Mind
Developing Workflows in VS: Part 3 - Five Steps for Developing Your Workflow
Developing Workflows in VS: Part 4 - Design and Bind Your Forms
Developing Workflows in VS: Part 5 - Code Your Workflow
Developing Workflows in VS: Part 6 - Deploy and Debug your workflow
Developing Workflows in VS: Part 7 - Summary and Final Thoughts

Robert Bogue [MVP] about SharePoint Workflow Quirks:
More SharePoint Workflow Quirks – Tasks, Debugging, Content Types and History Pages
More on SharePoint, Workflow, and DelayActivity

Other intresting blogposts:
What About Workflow and ASPX Forms?

Welcome To 2007!

Happy New Year and welcome to the Year of Bond, James Bond ;-)

The basic principles and usage of NHibernate by Maarten Balliauw

Maarten Balliauw wrote an article (written in Dutch) on the basic principles and usage of NHibernate, an ORM-mapper for the .NET platform. You have to readhis article!

Checkout his blog post about his article: here

Visual Studio 2005 extensions for .NET Framework 3.0 (Windows Workflow Foundation) RTM BUILD

Needed when developing Workflows with VS 2005 for Sharepoint 2007 RTM:

Download Visual Studio 2005 Extensions for Windows Workflow Foundation (EN).exe

You can still use the ECM Starter Kit for B2TR, download here

Using CAML to filter a infopath published boolean field (from a sharepoint list)

In a infopath form we have a boolean field called Draft, we publish the form to a sharepoint list, and we want to filter that list using Caml queries:
Which value should the BOOLEANVALUE have to succeed the query?
False/True ? Yes/No ? 0/1 ?
What I noticed is, when I published the infopath form the boolean type in intopath will be a Yes/No Type in the sharepoint list.....

So the Caml query will not work with BOOLEANVALUE = False/True Or Yes/No , you have to use 0 or 1...

Implement the CAML query into code:

StringBuilder camlBuilder = new StringBuilder();

string queryText = camlBuilder.ToString();

SPWeb site = SPContext.Current.Web;
SPList list = site.Lists["Mail"];
SPQuery query = new SPQuery();
string queryText =""
query.Query = queryText;

results = list.GetItems(query);
foreach (SPListItem item in results)
{..............}

If you put the query Tag as root tag into the query text, you will receive all items, zo don't put it there, some stupid guy I know very good did that ;-)

Also check this out:
U2U CAML Query Builder and Execution Tool (+download)

SPListItem looses Property data type when publishing Infopath form to a sharepoint list (MOSS 2007 beta2TR)

When you publish a Infopath Form to a sharepoint list, the Infopath form contains some fields (text and date(time) data types). These fields are copied to a sharepoint list when you publish the form to it.

You should think sharepoint keeps the data types like in the infopath form, but this isn't, I noticed that the date(time) data type is just a string/text field in the sharepoint list!

The strange thing is that when you add a column in the published list manualy (for example a datetime field), it will keep the data type and not change it to a string.

I noticed it when a wanted to perform an update an a field called ApprovalDate (Date Datatype) in a Web Part:

SPSite site = new SPSite("http://......");
SPListItemCollection results = site.Lists["InfopathPublishedList"].Items;
foreach (SPListItem item in results)
{
     item.Properties["ApprovalDate"] = DateTime.Today;//DateTime.Today.ToString();
 item.Update();
}

This code failed when I did this on the datetime field published by infopath:

Error:Specified data type does not match the current data type of the property. at Microsoft.SharePoint.Utilities.SPUtility.UpdateArrayFromHashtable(Object& o, Hashtable ht) at Microsoft.SharePoint.SPListItem.PrepareItemForUpdate(Guid newGuidOnAdd, Boolean bMigration, Boolean& bAdd, Boolean& bPublish, Object&
objAttachmentNames, Object& objAttachmentContents, Int32& parentFolderId) at Microsoft.SharePoint.SPListItem.UpdateInternal(Boolean bSystem, Boolean bPreserveItemVersion, Guid newGuidOnAdd, Boolean bMigration,
Boolean bPublish, Boolean bNoVersion, Boolean bCheckOut, Boolean bCheckin, Boolean suppressAfterEvents) at Microsoft.SharePoint.SPListItem.Update()

This doesn't happen if the ApprovalDate is added by create column in the list.

So watch out, and as you notice in the picture below: It ain't what it look like........

System.Web.UI.WebControls.WebControl doesn't fire all events

During the development of a ServerControl for a masterpage in a Sharepoint site, I added some eventhandlers in the CreateChildControls(): DayRender, VisibleMonthChanged and SelectionChanged.

After debugging, I noticed that only the DayRender event worked. I googled sites and newsgroups to find a solution, but I didn't find an answer....
After sending this problem to a colleague(thanks to: Sam), he answered this:

If you inherit controls from the WebControl class, you will get problems with events and state. So if you need dynamic controls, let them inherit from the CompositeControl class, this class is special made for controls that contains other controls.

At the CompositeControl MSDN page I found this:
The CompositeControl class is an abstract class that provides naming container and control designer functionality for custom controls that encompass child controls in their entirety or use the functionality (STATE AND EVENT HANDLING?!!?) of other controls.

Below some code of a custom Calendar that inherit from CompositeControl :

public class MailCalendar : System.Web.UI.WebControls.CompositeControl

{
        private System.Web.UI.WebControls.Calendar ctlCalendar;
      
       protected override void Render(HtmlTextWriter writer)
      {
            this.EnsureChildControls();
            this.ctlCalendar.RenderControl(writer);
      }
    
     protected override void CreateChildControls()
    {
           this.Controls.Clear();
           this.ctlCalendar = new System.Web.UI.WebControls.Calendar();
           ctlCalendar.VisibleDate = DateTime.Today; this.ctlCalendar.DayRender _
              += new DayRenderEventHandler(ctlCalendar_DayRender);            
         
           this.ctlCalendar.VisibleMonthChanged _
             += new MonthChangedEventHandler(ctlCalendar_VisibleMonthChanged); 
         
           this.ctlCalendar.SelectionChanged _
             += new EventHandler(ctlCalendar_SelectionChanged); this.Controls.Add(ctlCalendar);
    }

     void ctlCalendar_SelectionChanged(object sender, EventArgs e)
    {
           this.Context.Response.Redirect(.......);
     }

      void ctlCalendar_VisibleMonthChanged(object sender, MonthChangedEventArgs e)   
     {
        ctlCalendar.VisibleDate = e.NewDate;
     }
      
     void ctlCalendar_DayRender(object sender, DayRenderEventArgs e)
    {
           // Set date to bold if its today
            Style boldStyle = new Style();
            boldStyle.Font.Bold = true;

           if (e.Day.Date == DateTime.Today)
           { e.Cell.ApplyStyle(boldStyle); }
     }
}

More info: Webblog ScottGu

Writing Custom Web Parts for SharePoint 2007

On Scott Guthrie's Blog you can find a post with lots of info about "Writing Custom Web Parts for SharePoint 2007"