Converting String to Int with Swift

Question

The application basically calculates acceleration by inputting Initial and final velocity and time and then use a formula to calculate acceleration. However, since the value

Answer 1

for Swift3.x

extension String {
    func toInt(defaultValue: Int) -> Int {
        if let n = Int(self.trimmingCharacters(in: CharacterSet.whitespacesAndNewlines)) {
            return n
        } else {
            return defaultValue
        }
    }
}