[quote user="Zhen Li"]I tried to create a text element. I got a return value which says"it did not have the force text node flag".[/quote]
If you look in header file ...\SDK\include\DgnPlatform\TextBlock\TextAPICommon.h you can read the comment about #define TEXTBLOCK_TO_ELEMENT_RESULT_Empty: An element was not created because an empty TextBlock was provided (and it did not have the force text node flag).
Perhaps your TextBlock is empty?