US Weekly reports Ben Affleck took a selfie with another attendee and got into character as Batman.
The fan taking the pic said, "It’s nice to take a picture with Batman."
Ben Affleck then replied in his Batman voice: "Nice jacket."
Ben Affleck also recently told US Magazine that Batman might be helping out Ezra Miller as The Flash.
"[Batman is] sort of the ultimate loner, but he’s really trying to make it work and develop a good relationship with all of them. He might be a mentor to The Flash," Affleck said.
Ben Affleck next appears as Batman in Justice League this November.
Justice League has a November 17, 2017 release directed by Zack Snyder, with the story by Chris Terrio and Zack Snyder, the screenplay by Chris Terrio and Joss Whedon, and stars Ben Affleck as Batman, Henry Cavill as Superman, Gal Gadot as Wonder Woman, Jason Momoa as Aquaman, Ezra Miller as The Flash, Ray Fisher as Cyborg, J.K. Simmons as Commissioner Gordon and Willem Dafoe an Atlantean, Nuidis Vulko.
Fueled by his restored faith in humanity and inspired by Superman’s selfless act, Bruce Wayne enlists the help of his newfound ally, Diana Prince, to face an even greater enemy. Together, Batman and Wonder Woman work quickly to find and recruit a team of metahumans to stand against this newly awakened threat. But despite the formation of this unprecedented league of heroes—Batman, Wonder Woman, Aquaman, Cyborg and The Flash—it may already be too late to save the planet from an assault of catastrophic proportions.