问题
We are developing a VSTO application and we need this kind of feature group selected text as seen on the screenshot. We are able to do it by modifying the slide1.xml of an existing powerpoint file by changing the datatype of a:fld xml tag but question is how can we do it on runtime? When the presentation is just newly opened? Thanks for the answer.
来源：https://stackoverflow.com/questions/59266899/c-sharp-vsto-powerpoint-add-text-as-field