How to check if a text field is empty or not in swift

Solution 1:

Simply comparing the textfield object to the empty string "" is not the right way to go about this. You have to compare the textfield's text property, as it is a compatible type and holds the information you are looking for.

@IBAction func Button(sender: AnyObject) {
    if textField1.text == "" || textField2.text == "" {
        // either textfield 1 or 2's text is empty
    }
}

Swift 2.0:

Guard:

guard let text = descriptionLabel.text where !text.isEmpty else {
    return
}
text.characters.count  //do something if it's not empty

if:

if let text = descriptionLabel.text where !text.isEmpty
{
    //do something if it's not empty  
    text.characters.count  
}

Swift 3.0:

Guard:

guard let text = descriptionLabel.text, !text.isEmpty else {
    return
}
text.characters.count  //do something if it's not empty

if:

if let text = descriptionLabel.text, !text.isEmpty
{
    //do something if it's not empty  
    text.characters.count  
}

Solution 2:

Better and more beautiful use

 @IBAction func Button(sender: AnyObject) {
    if textField1.text.isEmpty || textField2.text.isEmpty {

    }
}

Solution 3:

another way to check in realtime textField source :

 @IBOutlet var textField1 : UITextField = UITextField()

 override func viewDidLoad() 
 {
    ....
    self.textField1.addTarget(self, action: Selector("yourNameFunction:"), forControlEvents: UIControlEvents.EditingChanged)
 }

 func yourNameFunction(sender: UITextField) {

    if sender.text.isEmpty {
      // textfield is empty
    } else {
      // text field is not empty
    }
  }

Solution 4:

if let ... where ... {

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
}

guard ... where ... else {

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.