Looking for TextPortion, TextField clarifications

Hello

While exploring the different TextPortion 
<https://www.openoffice.org/api/docs/common/ref/com/sun/star/text/TextPortion.html#TextPortionType> 
types I came across a few things that are unclear to me, and I was unable to find documentation for 
them. It would be great to have the community shed some light on this…

It seems that reference strings have somewhat different spaces: “_Ref498096146 “ and “ 
_Ref498096146” are the same reference (space after, space before) I assume?
What about the TextPortion types “TextFieldStart”, “TextFieldEnd", "TextFieldStartEnd"? I’ve seen 
them in documents, but can’t find documentation on them.
Calling getString() on a “TextFieldStart” returns a ^G and for “TextFieldEnd” a ^H. Their 
IsCollapsed property is False. What’s with that?
Given the list of text field services 
<https://wiki.openoffice.org/wiki/Documentation/DevGuide/Text/Text_Fields>, how can I find of which 
“type” a TextField 
<http://www.openoffice.org/api/docs/common/ref/com/sun/star/text/XTextField.html> object is? Should 
I really iterate over all services and check if an object implements one (or more) of the services?
In MS Word, a field’s “code” can be something like { PAGEREF _Ref498098146\h} (or NOTEREF, or REF). 
How are these reference kinds represented in the OO object model?

Thanks!
Jens

--
Jens Tröger
http://savage.light-speed.de/ <http://savage.light-speed.de/>