EN v DANS

Question

Thought “dans” was used when it is an event in the future????  Am I wrong to assume this???

Chris Wirt · Accepted Answer

Using en as a temporal preposition means "whithin a certain timeframe", which can also be translated as "in" (although "within" is usually better), just as dans. However, they are not interchangeable.
Nous mangeons dans une heure. -- We're eating in one hour (if it is 11 am now, we will eat at noon).Nous mangeons en une heure. -- We are eating within one hour (no matter what time it is when we start eating, we'll be finished within one hour).

Maarten Kamp · Answer

It is, but this is not exclusive to “dans”, and it is used in the way Chris notes.