.net - How to cleanly save richtextbox content? -

i've got problem : creating text editor, save richtextbox content in rtf file. i'm ok, test it, and, adding text alignement option, release alignement not saved in rtf file ! said, know how save cleanly text, i.e. saving fonts properties text alignement ?

you can try this: file.writealllines(filename, richtextbox1.lines);

or this: rtftextbox.savefile(filename);

add richtextboxstreamtype e.g.

rtftextbox.savefile(filename, richtextboxstreamtype.richtext); 

or

rtftextbox.savefile(filename, richtextboxstreamtype.texttextoleobjs);