Slapping during Confirmation?

Slapping is not part of the rite of confirmation. Paul Turner, in his book Ages of Initiation, published by (Collegeville, MN) The Liturgical Press, 2000 gives the following information on this history of this:

William Durandus put the slap into the confirmation rite in his pontifical
(1292-95). He explains it in the Explanation of the Divine Offices, 6:84,1.6.8
Then the bishop strikes the one confirmed on the face. First,
so that he or she may more firmly keep the memory that this sacrament has
been received. Second, because this sacrament is given to the baptized for
the strengthening of faith; as has formerly been said, that if one is
clearly so strong in the faith received in baptism, he or she will also
further not be embarrassed to confess the name of Christ before anyone. Third,
this strike represents the imposition of hands, because the apostles used
to confirm through the imposition of a hand. Fourth, it frightens the evil
spirit that it may flee and not dare to return, as blessed Benedict did by
means of a slap, freeing a monk who was troubled by an evil spirit, as is
read in the Dialogues of Gregory, book 2, heading 32.I'm convinced he got the idea from the Order of Becoming a Knight, which appears in the 13th c. Pontifical of the Roman Curia, appendix 4, 6f:

[After the prayer] the aforesaid lord archpresbyter or prior of the
canons gives a slap or a blow to the aforesaid candidate for knighthood.
When this has been done, he says a prayer over him.
God, who have always bestowed victory from heaven on your faithful, grant
we ask to this man, N., your servant, and to all those waging your wars
to overcome the evil of invisible armies by the strength of your power, and
to trample the impudence of visible armies, that when the pride of both
has fled away, your church may flourish with the joy of unity and peace.
Through Christ our Lord.