ASP.NET connect date and time?

Question

ASP.NET

There is a field in the model (public Datetime StartTime )
And there are two fields on the input form:
One is input type=date, the other is input type=time (for date and time, respectively)

It would be necessary to connect them somehow when submitting the form, because Firefox does not support datetime- local, where you can enter a full date in one field, which is infuriating.

Can anyone come across?