Zatanna

Earth-One / Post-Crisis / New Earth

 * 1) Ron was a boyfriend of Zatanna's at one point (Zatanna miniseries, 1985)
 * 2) Nick Necro - These two dated at one point.When Nick became obsessed with gaining new magic, Zatanna became distanced from him and fell in love with Constantine.
 * 3)  John Constantine  These two fell for each other when she was stil dating Nick Necro, whom she left for him. When Zatanna was kidnapped by Nick and Felix Faust, Constantine went on a crusade to find her, all while the Earth was falling into ruin. To the world-weary Constantine, saving the world is a second priority as he'd rather die than live without Zatanna. Their reunion is short-lived however, as Constantine backs down out of spite towards a demon that helped them stop Felix and Nick. Outraged at Constantine's disregard for an ally because he was a demon, Zatanna and Constantine break up.

Nick would then spite the two of them whenever he could. His newfound hatred of Zatanna has since reached the point where he allied himself with Felix Faust and the two of them used Zatanna as a power source for a new magic-fuelled machine.
 * 1)  Bruce Wayne / Batman  - Despite the fact that she had betrayed his trust and wiped his memory years earlier, Bruce later forgave her. They then began to fall for each other, and contemplated a relationship. But Zatanna said she could not be with a man who cared more for his demons than he did her.

Future's End

 * 1)  Etrigan  and Zatanna are a couple.

DCAU

 * 1)  Bruce Wayne  and Zatanna fell for each other during his travels as he prepared to be Batman. They met years later after he had taken up the mantle. Even after becoming Justice League teammates, the flames never rekindled.

Young Justice

 * 1)  Dick Grayson / Robin  -  These two had, at first, a flirtatious relationship. They exchanged kisses at various points in the series before starting a serious relationship. At the begining of the series second season (also known as "Young Justice Invasion"), it's revealed that their relationship was over. They remained as friends, which is shown when Nightwing shares with the team a magical​ artifact that Zatanna had gave him as a gift.

Justice League: Dark

 * 1)  John Constantine  - These two are shown having a previous relationship, and get back together by the film's end.