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ios - Why is Optional("Text") - Swift

I just started with Swift. So I created a simple application with a label, button and a text field. When you click the button, the app has to change the label with the text of the text field.

class ViewController: UIViewController {
    @IBOutlet weak var textLabel: UILabel!
    @IBOutlet weak var textField: UITextField!

    @IBAction func updateButton(sender: UIButton) {
        textLabel.text = "Hi (textField.text) "
    }

The result is

Hi Optional("TextOfTextField")

Okay. So it's a very simple question.

I hope someone can help me.

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The text of your textField is an optional value because a text field can sometimes be empty. So, use an if let to unwrap the variable and make sure it's not nil — otherwise your program could crash:

if let text: String = textField.text {
   textLabel.text = text
}

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