Can't pass Date to NSPredicate(format: …) without “as CVarArg”

问题

Is this how I'm supposed to pass a Date to NSPredicate.init(format predicateFormat: String, arguments argList: CVaListPointer).

let endDate = Date()
NSPredicate(format: "endDate == %@", endDate as CVarArg)

It looks kinda clumsy, and I suspect I'm doing something wrong.

回答1:

The %@ format expect a Foundation object as argument, compare "Predicate Format String Syntax" in the "Predicate Programming Guide".

Therefore you have to cast the overlay type Date back to its Foundation counterpart NSDate:

let endDate = Date()
let pred = NSPredicate(format: "endDate == %@", endDate as NSDate)

来源：https://stackoverflow.com/questions/39587046/cant-pass-date-to-nspredicateformat-without-as-cvararg