Swift if value is nil set default value instead

Question

I have this code part:

let strValue = String()
textfield.stringValue = strValue!

The problem is that strValue can be nil.

For this I check it like this:

if strValues.isEmpty() {
   textfield.stringValue = ""
} else {
   textfield.stringValue = strValue!
}

But I there an quicker and easier way to do this?

I read something like ?? to solve it. But I don't know how to use it?

UPDATE thanks a lot for the many feedbacks. now i unterstand the ?? operator, but how i realize it in this situation?

let person = PeoplePicker.selectedRecords as! [ABPerson]
let address = person[0].value(forProperty: kABAddressProperty) as?
        ABMultiValue
txtStreet.stringValue = (((address?.value(at: 0) as! NSMutableDictionary).value(forKey: kABAddressStreetKey) as! String))

how can i usee the ?? operator in the last line of my code?

UPDATE 2 Okay i got it!

txtStreet.stringValue = (((adresse?.value(at: 0) as? NSMutableDictionary)?.value(forKey: kABAddressStreetKey) as? String)) ?? ""

Answer 1

you can do like this but your strValue should be optional type

let strValue:String?
textfield.stringValue = strValue ?? "your default value here"