Importing CDO.dll and still can't get headers from mail items using C#

[Andy Baldwin]

So, I have the following function defined in C#

public string InternetHeaders(Outlook.MailItem mi) {
object missingVal = System.Reflection.Missing.Value;
MAPI.Session session = new MAPI.SessionClass();
session.Logon("", missingVal, missingVal,
missingVal, missingVal,
missingVal, missingVal);
MAPI.Message m = (MAPI.Message)session.GetMessage(mi.EntryID,"");
System.Console.WriteLine(m.Fields);
MAPI.Fields fields = (MAPI.Fields)m.Fields;
string headers = fields["&H7D001E"];
return null;
}

MAPI is my CDO.dll reference, and Outlook is the Outlook API
reference. The problem lies in the second to last line where I am
attempting to get the message headers. Slipstick refers me to

http://support.microsoft.com/?kbid=194870

which gives a VB example in which it shows using the fields collection
like a c# indexer (which is what this code is based on). Problem is
that using either square brackets or parenthesis both give me build
errors ("Cannot apply indexing with [] to an expression of type
'MAPI.Fields'" or "'fields' denotes a 'variable' where a 'method' was
expected"). My autocomplete/tooltip is inactive when I attempt to use
the [] or () as well. I then additionally tried the get_item method
like so:

string headers = (string)fields.get_Item((object)0,(object)"&H7D001E");

assuming that the second argument called propID is the same everywhere
and got

An unhandled exception of type
'System.Runtime.InteropServices.COMException' occurred in mscorlib.dll
Additional information: [Collaboration Data Objects -
[MAPI_E_NOT_FOUND(8004010F)]]

I looked up that MAPI_E_NOT_FOUND error with no real luck. I have read
somwhere (although I can't find it again) that there were problems
using CDO under .Net. Is this true? Can anyone else suggest a quick
way to get the full message headers in .Net from an Outlook.MailItem?
I wanna parse this info and keep it to analyze for spammer trends.

Thanks in advance!!

Andy Baldwin

 

[Vadim Melnik]

Hi Andy,

string headers = (string)fields.get_Item((object)0,(object)"&H7D001E");

What if you call it as listed below, does it help?
string headers = (string)fields.get_Item("&H7D001E", null);

string headers = (string)fields.get_Item("&H7D001E",
System.Reflection.Missing.Value);


...
Regards,
Vadim.

 

[Andy Baldwin]

What if you call it as listed below, does it help?

string headers = (string)fields.get_Item("&H7D001E", null);

Gives a type 'System.Runtime.InteropServices.COMException'
Additional information: Parameter not found.

string headers = (string)fields.get_Item("&H7D001E",
System.Reflection.Missing.Value);

gives same exception about the MAPI_E_NOT_FOUND

The parameter list of get_Item is "object index, object PropsetID". I
was under the assumption that "&H7D001E" was a PropsetID so I tried
reversing the order of the parameters in your two calls, and
subsequently got another parameter not found exception and a type
mismatch exception respectivly (to the order above).

I have also in my spare time here watched the new MAPI.Message object
and verified that although I don't have a StoreID in my call to get
the message

MAPI.Message m = (MAPI.Message)session.GetMessage((Outlook.MailItem)mi.EntryID,"");

I am indeed getting the correct MAPI.Message. So that shouldn't be the
problem, right?

I had dreams about this last night too. Why isn't this as easy as it
should be? There should just be a string property named "headers" on
the message object (like the sender and other properties??).

Any more suggestions or hints are greatly appreciated!

Andy

 

[Vadim Melnik]

Hi Andy,

OK, here is idl definition for MAPI::Fields::Item

<idl>
[id(0x00000015), propget, helpstring("The Item property returns a single
Field object from the Fields collection.")]

VARIANT Item(

[in] VARIANT Index,

[in, optional] VARIANT PropsetID);

</idl>


And documentation snip

<doc>
objFieldsColl.Item(index)
objFieldsColl.Item(proptag)
objFieldsColl.Item(name [, propsetID] )
objFieldsColl

Required. Specifies the Fields collection object.

index
Integer. Value must be greater than 0 and less than or equal to 65,535
(&HFFFF). Specifies the index within the Fields collection.

proptag
Long. Value must be greater than or equal to 65,536 (&H10000). Specifies the
property tag value for the MAPI property to be retrieved.

name
String. Contains the custom name of the user-defined property, or a string
representation of the of its property tag.

propsetID
Optional. String....

</doc>


Perhaps first paramter should be a number, not a string?:

Int32 index = 0xH7D001E;
MAPI.Field headers = fields.get_Item(index, System.Reflection.Missing.Value)
as MAPI.Field;

...
Cheers,
Vadim.

 

[Andy Baldwin]

WOO HOO, I did some further searching and found a post

http://www.google.com/groups?hl=en&[email protected]#link7

that mentions that he was able to get something that looked like the
following to work:

string headers = ((MAPI.Field)fields.get_Item(MAPI.CdoPropTags.CdoPR_TRANSPORT_MESSAGE_HEADERS,
System.Reflection.Missing.Value)).Value.ToString();

MAPI.CdoPropTags is a enumeration that gives out all those funky hex
notations. This worked! Can't really tell why, It has something to do
with the cast to a Field object, and using that enumeration instead.
Really wierd problem, but thanks for all of your help!!

AB