The solution is quite simple,
I just add e.Handle like this :
PasteData(Clipboard.GetText());
e.Handle = true;
this means that all enters with be handled by humain.
In fact, the problem comes from the fact that it not only created table and copy data from the table to gridview, but also handled the "Ctrl + V" which meands copied something or entered the char "V" as well.
Thank you for all your help!!