Hello LeonidS !
That code work fine,thanks. I could have guessed for myself that one should use BxDolService :: call (...);
Now I got another one question. Can I edit some posts if I know $iContentId?
I tried to use 'entity_edit' by analogy with the previous code, but it not work.

Can you tell me which function I need use for that?

I looked code and couldn't find analog addData() function for edit action in BxBaseModGeneralFormsEntryHelper.php. Is it possible?