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

An Int in Swift contains an initializer that accepts a String. It returns an optional Int? as the conversion can fail if the string contains not a number.

By using an if let statement you can validate whether the conversion succeeded.

So your code become something like this:

@IBOutlet var txtBox1 : UITextField
@IBOutlet var txtBox2 : UITextField
@IBOutlet var txtBox3 : UITextField
@IBOutlet var lblAnswer : UILabel

@IBAction func btn1(sender : AnyObject) {

    let answer1 = "The acceleration is"
    var answer2 = txtBox1
    var answer3 = txtBox2
    var answer4 = txtBox3

    if let intAnswer = Int(txtBox1.text) {
      // Correctly converted
    }
}