how to remove an existing TDF_Label object in a TDocStd_Document?

Dear Wu.

It is not possible to remove the tag from the existed OCAF tree, You can only remove the attributes inside the tree, but ID will be not removed, it will stay, but empty.

For removing attributes, please use method of TDF_Label::ForgetAllAttributes

Best regards, Commenter-1.

it works. thank you.