washer machine emptying through the dishwasher?

hi, when my washer machine empties it fills up my dishwasher and leaks all over my kitchen floor. My dishwasher constantly has water in the bottom of it now (i have searched for blockages inside the dishwasher) and i cant get it to go through a cycle. The light is on but nothing happens?
has this happened to anyone before, can anyone please help?

Thank you