Swift 3:
if let _text = theTextField.text, _text.isEmpty {
// _text is not empty here
}
Swift 2:
if let theText = theTextField.text where !theTextField.text!.isEmpty {
// theText is not empty here
}
You can also use the keyword guard
:
Swift 3:
guard let theText = theTextField.text where theText.isEmpty else {
// theText is empty
return // or throw
}
// you can use theText outside the guard scope !
print("user wrote \(theText)")
Swift 2:
guard let theText = theTextField.text where !theTextField.text!.isEmpty else {
// the text is empty
return
}
// you can use theText outside the guard scope !
print("user wrote \(theText)")
This is particularly great for validation chains, in forms for instance. You can write a guard let
for each validation and return or throw an exception if there's a critical error.