Does an expert have to provide their opinion in an affidavit?

From paragraph 17, I quote, “The defendants are correct that an expert report must provide his or her opinion in an affidavit. In Toronto Dominion Bank v. Schrage [2009] No. 3636 Strathy J., as he then was, remarked upon the necessity of a sworn affidavit in the context of expert evidence at para 39: This is not a formality. On a motion for summary judgment the court is entitled to sworn evidence and, in the case experts, that the evidence be given by the expert and not filtered through the hearsay evidence of the party.”