How do I check for an empty or nil string in Swift?

[kjmcneish]

Here's an extension you can add to the String class that checks for an empty (after trimming whitespace) or nil string:

Code: [Select]

extension String {
   public static func isNilOrEmpty(string: String?) -> Bool {
       
        switch string?.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceCharacterSet()) {
        case .Some(let nonNilString):
            return nonNilString.isEmpty
        default:
            return true
        }
    }
}
You can use it like this:

Code: [Select]

var isEmpty = String.isNilOrEmpty(myString)
All the best!
Kevin McNeish
Author of Learn to Code in Swift: https://itunes.apple.com/us/book/learn-to-code-in-swift/id942956811?mt=11