The Archives of Ontario holds marriage registrations and the indexes (where they exist) from 1801 to 1942.
Ancestry indexes and makes images of the original record available as part of their Canadian collection. Free access is available at all Ontario public libraries.
In January, Ancestry updated the collection to 1939. It’s now available up to 1942. Wartime was a good time for marriages.
For more details on these marriage records, start by consulting https://www.archives.gov.on.ca/en/tracing/marriage_registrations.aspx