mstehle: The CDOs and CDONTS of Messaging Development : HOWTO

HOWTO: Sample Transport Agent – Add Headers, Categories, MAPI Props, Even Uses a Fork!

mstehle — Wed, 14 Jan 2009 00:50:33 GMT

Welcome to my first in depth Exchange Transport Agent sample! If you are not familiar with Exchange Transport Agents this blog post is a great place to start. I created a sample Transport Agent for a customer a while ago that I recently added commenting to and cleaned up so it could serve as a general demo suitable for this blog. The focus of this sample is to illustrate a several techniques but no necessarily serve as a template or best practice for writing transport agents in general. The key techniques illustrated are:

Forking a message in the “OnSubmittedMessage” event to process a messages individually for each recipient.
Adding a custom header to a message.
Adding a Keywords (also known as Category) header to a message
Adding a custom named property to a MAPI message

The comments in the code speak for themselves so I won’t walk through it all. There are two very important notes regarding the Keyword header and adding MAPI properties that I want to emphasize though.

The Keywords Header is Removed By Default

If you are you trying to add the Keywords header in a transport agent or even just when sending MIME messages to Exchange 2007 keep in mind that this header is translated into Categories which are removed by default during content conversion. If you really need this functionality though, you can turn this off using the Set-TransportConfig cmdlet and setting ClearCategories to $false. Click here to read more.

If You Don’t Get TNEF, You Don’t Have TNEF

There is no API to convert MIME messages to TNEF within a transport agent. The TNEF body part must be a full representation of the message being submitted to Exchange. You can’t have a complex MIME message with a TNEF body part that simply adds a MAPI property or two. Messages that are submitted from outside the organization will mostly like not have TNEF, there is no mechanism to create a representative TNEF body part for these messages and then append properties.

One final note is that this sample logs information out to a text file on the system. Keep in mind that transport agents run in the context of the Exchange Transport Service which is typically Network Service. In this case, the Network Service account would need write permissions to whatever folder the log file is configured to write to.

Enjoy…

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using Microsoft.Exchange.Data.Transport;
using Microsoft.Exchange.Data.Transport.Routing;
using Microsoft.Exchange.Data.Common;
using Microsoft.Exchange.Data.Mime;
using Microsoft.Exchange.Data.ContentTypes.Tnef;

namespace MyRoutingAgent
{

    public sealed class MyRoutingAgentFactory : RoutingAgentFactory
    {
        public override RoutingAgent CreateAgent(SmtpServer server)
        {
            return new MyRoutingAgent();
        }
    }

    public class MyRoutingAgent : RoutingAgent
    {
        // Place this text in the subject to test the agent
        public const string TEST_TOKEN = "[TEST]";
        public const string LOG_FILE_PATH = @"C:\Users\Administrator\Desktop\MyRoutingAgent\MyRoutingAgent.log";

        public MyRoutingAgent()
        {
            this.OnRoutedMessage += new RoutedMessageEventHandler(MyRoutingAgent_OnRoutedMessage);
            this.OnSubmittedMessage += new SubmittedMessageEventHandler(MyRoutingAgent_OnSubmittedMessage);
            this.OnResolvedMessage += new ResolvedMessageEventHandler(MyRoutingAgent_OnResolvedMessage);
        }

        void MyRoutingAgent_OnSubmittedMessage(SubmittedMessageEventSource source, QueuedMessageEventArgs e)
        {
            // Don't process EVERY message...
            if (e.MailItem.Message.Subject.Contains(TEST_TOKEN))
            {
                // If we have multiple recipients, fork the message to process each recipient seperately...
                if (e.MailItem.Recipients.Count > 1)
                {
                    LogMessage("OnSubmittedMessage", e.MailItem, "Forking message with " + e.MailItem.Recipients.Count + " recipients.");

                    int count = 0;
                    while (e.MailItem.Recipients.Count > 1)
                    {
                        // Create an individual forked message for each recipient...
                        EnvelopeRecipient recip = e.MailItem.Recipients[e.MailItem.Recipients.Count - 1];
                        List<EnvelopeRecipient> recips = new List<EnvelopeRecipient>();
                        recips.Add(recip);
                        source.Fork(recips);
                        count++;
                    }

                    // This should always be one.
                    LogMessage("OnSubmittedMessage", e.MailItem, "Forked " + count + " messages.");
                }
                else
                {
                    LogMessage("OnSubmittedMessage", e.MailItem, "Single recipient, no forking needed.");
                }
            }
        }

        void MyRoutingAgent_OnResolvedMessage(ResolvedMessageEventSource source, QueuedMessageEventArgs e)
        {
            // Don't process EVERY message...
            if (e.MailItem.Message.Subject.Contains(TEST_TOKEN))
            {
                MimePart tnefPart = e.MailItem.Message.TnefPart;
                if (tnefPart != null)
                {
                    LogMessage("OnResolvedMessage", e.MailItem, "TNEF");
                }
                else
                {
                    LogMessage("OnResolvedMessage", e.MailItem, "No TNEF");
                }
            }
        }
        
        void MyRoutingAgent_OnRoutedMessage(RoutedMessageEventSource source, QueuedMessageEventArgs e)
        {
            // Don't process EVERY message...
            if (e.MailItem.Message.Subject.Contains(TEST_TOKEN))
            {
                if (e.MailItem.Recipients.Count == 1)
                {
                    LogMessage("OnRoutedMessage", e.MailItem, "Processing message sent to " + e.MailItem.Recipients[0].Address.LocalPart + ".");

                    // If we haven't already processed this message...
                    if (e.MailItem.Message.MimeDocument.RootPart.Headers.FindFirst("MyHeader") == null)
                    {
                        ProcessMailItem(e.MailItem);
                    }
                    else
                    {
                        LogMessage("OnRoutedMessage", e.MailItem, "Already processed this message, skipping.");
                    }
                }
                else
                {
                    LogMessage("OnRoutedMessage", e.MailItem, "Unexpected number of recipients, " + e.MailItem.Recipients.Count.ToString() + ".");
                }
            }
        }

        /// <summary>
        /// Add a custom header, keyword header, and MAPI
        /// named property into PS_PUBLIC_STRINGS if there
        /// is a TNEF body part.
        /// </summary>
        private void ProcessMailItem(MailItem item)
        {
            // Modify the subject of this message to ensure the
            // fork worked.  Append the first recipient name to the 
            // subject.  This should match the mailbox name the
            // message is delivered to.
            item.Message.Subject = item.Message.Subject + "| To: " + item.Recipients[0].Address.LocalPart;

            MimeDocument mdMimeDoc = item.Message.MimeDocument;
            HeaderList hlHeaderlist = mdMimeDoc.RootPart.Headers;
            MimeNode lhLasterHeader = hlHeaderlist.LastChild;

            // Add a custom header
            TextHeader nhNewHeader = new TextHeader("MyHeader", "MyHeaderValue");
            hlHeaderlist.InsertBefore(nhNewHeader, lhLasterHeader);

            // Add the Keywords header to set a Category in Outlook/OWA.
            // *** INFO ***
            // Keywords (also known as Categories) are stripped from
            // message by default.  This can be disabled using the 
            // "Set-TransportConfig –ClearCategories $false" cmdlet.
            // (http://technet.microsoft.com/en-us/library/bb124151.aspx)
            TextHeader nhNewKeywords = new TextHeader("Keywords", "1");
            hlHeaderlist.InsertBefore(nhNewKeywords, lhLasterHeader);

            MimePart tnefPart = item.Message.TnefPart;

            // Without a TNEF body part, we can't do this step.
            // There is no way to create a TNEF body part from
            // scratch if Exchange isn't giving us one.  Most
            // mail that comes from the internet won't have TNEF.
            if (tnefPart != null)
            {
                TnefReader reader = new TnefReader(tnefPart.GetContentReadStream());
                TnefWriter writer = new TnefWriter(
                    tnefPart.GetContentWriteStream(tnefPart.ContentTransferEncoding),
                    reader.AttachmentKey,
                    0,
                    TnefWriterFlags.NoStandardAttributes);

                while (reader.ReadNextAttribute())
                {
                    if (reader.AttributeTag == TnefAttributeTag.MapiProperties)
                    {
                        writer.StartAttribute(TnefAttributeTag.MapiProperties, TnefAttributeLevel.Message);
                        writer.WriteAllProperties(reader.PropertyReader);

                        int tag;
                        unchecked
                        {
                            // The first four bytes of the tag is must be at least 0x8000 
                            // when setting a named property, the second determines the type. 
                            // http://www.cdolive.com/cdo10.htm
                            tag = (int)0x8000001E;
                        }

                        Guid PS_PUBLIC_STRINGS = new Guid("00020329-0000-0000-C000-000000000046");

                        writer.StartProperty(
                            new TnefPropertyTag(tag),
                            PS_PUBLIC_STRINGS,
                            "MyProp");
                        writer.WritePropertyValue("Hello!");
                    }
                    else
                    {
                        writer.WriteAttribute(reader);
                    }
                }

                //  Close writer
                if (null != writer)
                {
                    writer.Close();
                }

                LogMessage("ProcessMailItem", item, "Added 'MyProp' to PS_PUBLIC_STRINGS.");
            }
            else
            {
                LogMessage("ProcessMailItem", item, "No TNEF, not adding property");
            }
        }

        private void LogMessage(string eventName, MailItem item, string message)
        {
            TextWriter tw = System.IO.File.AppendText(LOG_FILE_PATH);
            tw.WriteLine(DateTime.Now.Ticks + "\t" + eventName + " - " + item.Message.Subject + " - " + message);
            tw.Close();
        }
    }

}

HOWTO: Delete Search Folders and Interop with CDO 1.21 from Managed (.NET) Code

mstehle — Fri, 27 Jul 2007 18:28:00 GMT

The Outlook 2003 Object Model does not have anyway to delete Search Folders, although you can create them. The only way to delete them is to use CDO 1.21 code. However, it is not supported to run CDO 1.21 or MAPI code (yes, this includes ~~Redemption~~ any third party APIs or components you write that use MAPI/CDO 1.21 directly) *in-process* with managed .NET code. This means that simply wrapping the CDO 1.21 code below in a COM component is not enough, the code must live in its own process. The easiest way I know of to do that is hop back over to good ‘ole VB6 and create a very simple ActiveX EXE. This is a very simple way to run all CDO code in one process while the managed OOM code runs in another process (such as Outlook.EXE) without having to do too many configuration or deployment backflips.

In fact, the code below comes directly from an ActiveX EXE created to allow the deleting of Search Folders…

'-------------------------------------------------------

' DeleteSearchFolder

' mstehle, 07.27.07

'-------------------------------------------------------

' This CDO 1.21 code is hosted in an simple ActiveX EXE

' so that it can be called from a .NET application. The

' code runs in a seperate process which allows us to

' call it from the managed process without fear of memory

' issues.

'--------------------------------------------------------

Public Sub DeleteSearchFolder(ByVal strName As String)

Dim oSession As MAPI.Session

oSession = New MAPI.Session

' Assume we are already logged in to a session and

' piggy-back the session...

oSession.Logon, , False, False

Dim oFinderFolder As MAPI.Folder

oFinderFolder = GetFinderFolder(oSession)

' Throw error if folder not found

If oFinderFolder Is Nothing Then

Err.Raise(MAPI.CdoE_NOT_FOUND, "DeleteSearchFolder", _

"Finder folder not found.")

End If

Dim oSearchFolder As MAPI.Folder

oSearchFolder = GetFolder(strName, oFinderFolder)

' Throw error if folder not found

If oSearchFolder Is Nothing Then

Err.Raise(MAPI.CdoE_NOT_FOUND, "DeleteSearchFolder", _

"Search folder not found with name " & strName)

End If

' If found, delete it

oSearchFolder.Delete()

End Sub

Private Function GetFolder(ByVal strName As String, _

ByVal oParentFolder As MAPI.Folder) As Folder

Dim oFolder As MAPI.Folder

For Each oFolder In oParentFolder.Folders

If oFolder.Name = strName Then

GetFolder = oFolder

Exit For

End If

End Function

Private Function GetFinderFolder(ByVal oSession As MAPI.Session) _

As MAPI.Folder

If oSession Is Nothing Then

Err.Raise(MAPI.CdoE_LOGON_FAILED, _

"DeleteSearchFolder", "No session established.")

End If

' Get root mailbox store folder

Dim oInbox As MAPI.Folder

oInbox = oSession.Inbox

Dim oStore As MAPI.InfoStore

oStore = oSession.GetInfoStore(oInbox.StoreID)

Dim oRootFolder As MAPI.Folder

oRootFolder = oSession.GetFolder("", oStore.ID)

Dim oFolder As MAPI.Folder

For Each oFolder In oRootFolder.Folders

Debug.Print(oFolder.Name)

' In a PST the folder is called "Search Root", in an online

' profile it is called "Finder"

If oFolder.Name = "Finder" Or oFolder.Name = "Search Root" Then

GetFinderFolder = oFolder

Exit For

End If

End Function

HOWTO: Using CDOEXM in ASP.NET (.NET Framework 2.0 Walkthrough)

mstehle — Fri, 11 May 2007 22:13:00 GMT

I just finished updating a support document which walks through creating a simple COM+ component and ASP.NET page to illustrate how you have to use CDOEXM with ASP.NET due to impersonation limitations of CDOEXM...enjoy...

...Use all code in this post at your own risk, etc...

CDO for Exchange Management (CDOEXM) is a management API for Exchange 2000 and 2003. While using CDOEXM in an ASP or ASPX web application you may get unexpected Access Denied or Catastrophic Failure errors. This is because CDOEXM only supports process-level impersonation and not the thread-level impersonation required by a web application using Windows Integrated for example. Due to impersonation limitations of CDOEXM, the only method supported by Microsoft for using CDOEXM from ASP or ASPX is to create a COM component and register that component with component services (COM+) running the component in a specific user identity.

Below is a walkthrough of how to create a simple .NET component which wraps CDOEXM and ADSI code to create users and associate mailboxes. There is also a function to illustrate the security context of the component which you can compare to the context of your application. We will illustrate this difference in a simple ASP.NET web application.

Environment Setup

This walkthrough is based off of Exchange 2003 and Visual Studio 2005 running off of Windows 2003. The code in this walkthrough is C#.

This code should be run from a Windows Server 2003 client that has Exchange 2003 Administrative Tools installed if you are targeting Exchange 2003 or an Exchange 2000 server. If you are targeting an Exchange 2000 server, you could also use a Windows 2000 client that has Exchange 2000 Administrative Tools installed. The CDOEXM version that is included in Exchange 2003 must be used when you access Exchange 2003. The Exchange 2003 CDOEXM can also be used to access Exchange 2000. The CDOEXM library that is included in Exchange 2000 is not supported for accessing Exchange 2003.

Creating the C# Component

Build and configure a COM+ component to host the CDOEXM code and ensure that it is running with the credentials of a service account and not inheriting any credentials from the caller.

Create the project…

Start Visual Studio 2005
Select File->New->Project…
Under C#, select Windows
In the “Template Types” select “Class Library”
In the Name box type “CDOEXMComponent”
Click OK.
Add references to System.EnterpriseServices, System.DirectoryServices, CDOEXM (listed on the COM tab), and Active DS Type Library (also listed on the COM tab).

Sign and Create Interop Libraries for ActiveDS and CDOEXM…

1. Right click on the CDOEXMComponent project in the Solution Explorer and click properties. In the signing tab check the box to “Sign the assembly” and create a new strong name key called “CDOEXMComponent.snk”.

2. Still in the project properties window, select the Application tab and click “Assembly Information…”, check the box that says, “Make assembly COM-Visible”.

3. Open the AssemblyInfo.cs and add “using System.EnterpriseServices;” to the top and the following lines at the bottom of the file…

[assembly: ApplicationActivation(ActivationOption.Server)]

[assembly: ApplicationName("CDOEXMComponent")]

[assembly: Description("Simple CDOEXM Component Sample")]

Add the CDOEXMSample class…

Select the “Solution Explorer” view tab.

Rename the class1.cs file to “CDOEXMSample.cs”.

Remove the code generated by the Wizard.

Cut and past the code provided below:

using System;

using System.Collections.Generic;

using System.DirectoryServices;

using System.EnterpriseServices;

using System.Runtime.InteropServices;

using System.Text;

using ActiveDs;

using CDOEXM;

public class CDOEXMSample:

System.EnterpriseServices.ServicedComponent

{

public void CreateUserWithMailbox(string strFirstName,

string strLastName, string strSamName,

string strBaseContainer, string strHomeMDB)

{

// Start local variable definitions

DirectoryEntry oCont =

new DirectoryEntry("LDAP://" + strBaseContainer);

IADsContainer oDSCont = null;

IADsUser oUser = null;

IMailboxStore oMailBox = null;

try

{

oDSCont = oCont.NativeObject as IADsContainer;

oUser = oDSCont.Create("user",

string.Format("CN={0} {1}",

strFirstName, strLastName)) as IADsUser;

oUser.Put("sn", strLastName);

oUser.Put("givenname", strFirstName);

oUser.Put("samaccountname", strSamName);

oUser.SetInfo();

oUser.AccountDisabled = false;

oUser.SetInfo();

oMailBox = oUser as IMailboxStore;

oMailBox.CreateMailbox(strHomeMDB);

oUser.SetInfo();

}

finally

{

oCont.Dispose();

if (oDSCont != null)

{

Marshal.ReleaseComObject(oDSCont);

oDSCont = null;

}

if (oUser != null)

{

Marshal.ReleaseComObject(oUser);

oUser = null;

}

if (oMailBox != null)

{

Marshal.ReleaseComObject(oMailBox);

oMailBox = null;

}

public string GetIdentity()

{

AppDomain.CurrentDomain.SetPrincipalPolicy(

System.Security.Principal.PrincipalPolicy.WindowsPrincipal);

System.Security.Principal.WindowsPrincipal user =

System.Threading.Thread.CurrentPrincipal

as System.Security.Principal.WindowsPrincipal;

return user.Identity.Name;

}

Create and Configure the COM+ Component

1. Build the CDOEXMComponent project in Visual Studio

2. From the Visual Studio command prompt run “regsvcs CDOEXMComponent.dll”

3. Open “Component Services” from “Administrative Tools”

4. Under “Component Services”, “Computers”, “My Computer”, “COM+ Applications”, find “CDOEXMComponent” and right click on it then select “Properties”

5. On the security tab:

a. Under “Authorization” uncheck “Enforce access checks for this application”

b. Select “None” for “Authentication Level for Calls”

c. Select “Identify” for “Impersonation Level”

6. On the identity tab:

a. Configure “This user” as an account that has Exchange Admin privileges on your Exchange server. You could use the Administrator account for testing purposes.

7. Click OK

Create Web Application to Consume CDOEXMComponent

Create a folder and application files

1. Create a folder called “CDOEXMComponent” on the file system of your web server. For example, “C:\inetpub\wwwroot\CDOEXMComponent”.

2. Copy CDOEXMComponent.dll, Interop.ActiveDs.dll, and Interop.CDOEXM.dll from the output directory of the CDOEXMComponent project to a folder named “bin” under the folder you just created in Step 1.

3. Create a new file in the “CDOEXMComponent” folder called “web.config”

a. Copy the following XML and paste it in the web.config file

<?xml version="1.0"?>

<system.web>

<add assembly="System.DirectoryServices,

Version=2.0.0.0,

Culture=neutral,

PublicKeyToken=B03F5F7F11D50A3A"/>

</assemblies>

</compilation>

</system.web>

</configuration>

4. Create another file in the “CDOEXMComponent” folder called “Default.aspx”

a. Copy the following code and paste it in the aspx file

b. Notice you will have to change the variables to match your test environment

<%@ Page Language="C#" %>

// CreateUserWithMailbox Input, change to match

// your test environment.

string firstName = "Matt";

string lastName = "Stehle";

string samName = "mstehle";

string baseContainer = "CN=Users,DC=mstehle03,DC=extest,DC=microsoft,DC=com";

string homeMDB = "CN=Mailbox Store (MSTEHLEEX03),CN=First Storage Group,CN=InformationStore,CN=MSTEHLEEX03,CN=Servers,CN=First Administrative Group,CN=Administrative Groups,CN=First Organization,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=mstehle03,DC=extest,DC=microsoft,DC=com";

// Print out the security context of the web application

Response.Write(string.Format(

" Web Application Context: {0} ",

System.Threading.Thread.CurrentPrincipal.Identity.Name));

// Create component

CDOEXMSample obj = new CDOEXMSample();

try

{

obj.CreateUserWithMailbox(firstName, lastName,

samName, baseContainer, homeMDB);

Response.Write(" Mailbox Created! ");

}

catch (Exception ex)

{

Response.Write(" Error when creating mailbox... ");

Response.Write(string.Format("Message: {0} ", ex.Message));

Response.Write(string.Format("Stack Trace: {0} ", ex.StackTrace));

}

// Print out the security context of the component

Response.Write(string.Format(

" CDOEXMComponent Context: {0} ",

obj.GetIdentity()));

Create and Configure the virtual directory in IIS on your web server

1. Click Start, select “Run…” and type “inetmgr”, Click OK

2. Expand the “Web Sites” folder

3. Select a Web Site, right click and select New, “Virtual Directory…”

a. Click Next

b. For the alias, type “CDOEXMComponent”

c. Click Next

d. Set the appropriate path to the folder where you just created the ASPX file.

e. Click Next

f. Select Read and “Run scripts (such as ASP)”

g. Click Next

h. Click Finish

4. Right click the CDOEXMComponent virtual directory you just created and select Properties

a. Click the “Directory Security” tab

b. In “Authentication and access control” click the “Edit…” button

c. Uncheck “Enable anonymous access”

d. Check only “Integrated Windows Authentication” under “Authenticated access”

e. Click OK

f. Click OK

Talking a look at the results

When you access this page from another machine as different user than the administrator account configured in the COM+ component you will notice that the web application and the COM+ component are running in different security contexts. For example in my test, I was logged in a user called Green Giant and when I hit the web I got the following result…

Web Application Context: MSTEHLE03\ggiant

Mailbox Created!

CDOEXMComponent Context: MSTEHLE03\Administrator

…The key here is that Green Giant is just a simple User in my test domain. He has no permissions to create new Active Directory Users or Exchange mailboxes. However, all he has to do is authenticate against the domain to gain access to this web form. The web form makes the call to our COM+ component which always executes the CDOEXM code in the context of Administrator, not matter who the calling process is running as. Again, this is because CDOEXM does not support thread level impersonation.

Therefore it is very important to pay attention to the directory security configuration in IIS and what users will have access to the web application in this scenario as well as who has rights to create and make calls to the COM+ component. Anybody who can call this component can create a mailbox.

HOWTO: Determining the Owner of a Shared Folder

mstehle — Thu, 07 Sep 2006 21:27:00 GMT

The Outlook 2003 Object Model does not have much support for shared folders outside the GetSharedDefaultFolder function. One common question we get asked is, "Given an OOM MAPIFolder object that represents a shared folder, how can I determine who's the owner of that folder?". This is a common question from Outlook COM AddIn developers who are working with Inspectors and need to know what calendar a user is making changes in.

Like I said before, OOM doesn't have much support for shared folders so we came up with a hack to answer the question. The StoreID of the folder actually will contain the owner's information if you decode the binary string. The following code sample will pull the owner name out of the StoreID of a MAPIFolder object...

public string GetFolderOwner(Outlook.MAPIFolder oFolder)

{

if (oFolder == null) return "";

string storeID = oFolder.StoreID;

return ParseEntryID(storeID);

}

// Convert the EntryID to characters and parse out the

// owner name

private string ParseEntryID(string storeID)

{

string s = HexReader.GetString(storeID);

//TODO: These values might be different depending on

what you have named your groups in ESM

const string REG_EX = @"/o=First Organization/ou=First

Administrative Group/cn=Recipients/cn=(\w+)";

Match m = Regex.Match(s, REG_EX);

return m.Value;

}

Here is the code for the HexReader class…

/// <summary>

/// Simple class for reading a string containing Hex numbers

/// </summary>

public class HexReader

{

private HexReader()

{

// this class cannot be directly instantiated

}

// Given a string containing hex characters

// this function will return the actual string

// representation of that hex string

public static string GetString(string hexString)

{

System.Text.StringBuilder sb = new StringBuilder();

System.Text.StringBuilder sb2 = new StringBuilder();

for (int i = 0; i < hexString.Length; i = i + 2)

{

string s = hexString.Substring(i, 2);

try

{

int j = int.Parse(s, System.Globalization.NumberStyles.HexNumber);

char c = ConvertToCharacter(j);

sb.Append(c);

}

catch (System.Exception e)

{

System.Diagnostics.Debug.WriteLine(e.Message);

}

return sb.ToString();

}

private static char ConvertToCharacter(int CharCode)

{

char ch1;

if ((CharCode < -32768) || (CharCode > 0xffff))

{

// throw error

}

if ((CharCode >= 0) && (CharCode <= 0x7f))

{

return Convert.ToChar(CharCode);

}

try

{

int num1;

// get the current encoding

Encoding encoding1 = Encoding.GetEncoding(

Thread.CurrentThread.CurrentCulture.TextInfo.ANSICodePage);

if ((encoding1.GetMaxByteCount(1) == 1) &&

((CharCode < 0) || (CharCode > 0xff)))

{

// throw error

}

char[] chArray1 = new char[2];

byte[] buffer1 = new byte[2];

Decoder decoder1 = encoding1.GetDecoder();

if ((CharCode >= 0) && (CharCode <= 0xff))

{

buffer1[0] = (byte)(CharCode & 0xff);

num1 = decoder1.GetChars(buffer1, 0, 1, chArray1, 0);

}

else

{

buffer1[0] = (byte)((CharCode & 0xff00) / 0x100);

buffer1[1] = (byte)(CharCode & 0xff);

num1 = decoder1.GetChars(buffer1, 0, 2, chArray1, 0);

}

ch1 = chArray1[0];

}

catch (Exception exception1)

{

throw exception1;

}

return ch1;

}

HOWTO: How To Search mv.string Properties using WebDAV

mstehle — Thu, 20 Apr 2006 07:46:00 GMT

...I have posted a new WebDAV sample for using mv.string properties like Keywords and RRule in WHERE clauses, enjoy...

DAV: How To Search mv.string Properties

HOWTO: Bind to items from CDO/MAPI using WebDAV

mstehle — Wed, 01 Mar 2006 03:50:00 GMT

Summary

Using PR_URL_COMPNAME to bind to an item in WebDAV from CDO/MAPI involves understanding the encoding rules for the Exchange version where the item is homed. These rules are different and incompatiable between Exchange 2000, Exchange 2000 SP 1, and Exchange 2003. These rules are not documented and often require reverse engineering to properly encode URLs.

Reading proptag 0x670E001E via MAPI on a folder or item will return a value such as…

/-FlatUrlSpace-/ca09cf9efaad754e8a85909b04bb255c-12ee443

...which can be appended to a URL and used to access and item or folder via WebDAV…

http://server/exchange/mailbox/-FlatUrlSpace-/ca09cf9efaad754e8a85909b04bb255c-12ee443

More Information

Flat URLs do not have encoding and escaping rules and will work for folders and items in most every DAV operation with the following exceptions:

- as destination of MOVE or COPY operation
- as a source for a DELETE
- for OWA URL commands, e.g. "?cmd=[foo]"

...You are going to use this property in cases where you are stepping out of CDO 1.21 or MAPI code into WebDAV. The HREF in WebDAV is usually created from the subject that was typed in OL (messages created in OWA typically have a GUID file name). The subject in OL can contain characters that must be encoding for use with DAV similar to URL encoding. Rather than figure out those rules, you can use the Flat URL to get the item. The great thing about the proptag is that it is a direct link between MAPI and WebDAV...

...Enjoy...