Basic Idea, note that this only works in Swift 1.x (check out ParaSara’s answer to see how it works in Swift 2.x):
// toInt returns optional that's why we used a:Int? let a:Int? = firstText.text.toInt() // firstText is UITextField let b:Int? = secondText.text.toInt() // secondText is UITextField // check a and b before unwrapping using ! if a && b { var ans = a! + b! answerLabel.text = "Answer is \(ans)" // answerLabel ie UILabel } else { answerLabel.text = "Input values are not numeric" }
Update for Swift 4
... let a:Int? = Int(firstText.text) // firstText is UITextField let b:Int? = Int(secondText.text) // secondText is UITextField ...
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