c# - Issue with setting a DateTime? to null using ternary operator -

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possible duplicate:
type result conditional operator in c#

i working on pop-up modifying user, when ran following issue while attempting modify user's date of death :

in scenario, property death user datetime? (nullable date time).

user.death = (model.death != null) ? datetime.parse(model.death) : null;

so figured able check if value contained in model (model.death string) contained value, set date value, otherwise set null, demonstrated above.

however, unable use syntax, not allow me explicitly set user.death null, using ternary operator, although user.death = null worked fine.

solution used :

replaced : null : new nullable<datetime>()

i guess wondering, why unable explicitly set nullable datetime property null using ternary operator?

this doesn't work because compiler not insert implicit conversion on both sides @ once.

you want compiler convert datetime value datetime? on 1 side, , null datetime? on other side.
cannot happen.

if explicitly convert either half datetime?, other half implicitly convert too.


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