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iOS Build a Simple iPhone App with Swift Getting Started with Xcode Recap of Swift Basics

Jack Ferguson
Jack Ferguson
1,018 Points
Posted by Jack Ferguson
Jack Ferguson
1,018 Points

When I type optionalstring without the bang it still displays "hello" in the right bar. The bang doesn't do anything.

I declared the optional thus: var optionalString: String? = "hello" and in the right bar "hello" is displayed

1 Answer

Michael Liendo
Michael Liendo
15,326 Points
Michael Liendo
Michael Liendo
15,326 Points

when you type var optionalString: String? = "hello you're creating an optional (a variable that can either be nil or contain a value) and setting the value to a string (hello). When you use the bang, you're force-unwrapping the optional, telling the complier that when the variable is used it will always have a value (whether it be "hello" or otherwise). If you leave out the ? or the ! entirely, then it's no longer an optional, it's just a plain string with a value of hello. Hope that helps clear things up!