iPhone: Issue disabling Auto-Cap/autocorrect on a UITextField

Objective - C

-(void)textFieldDidBeginEditing:(UITextField *)textField
{
    textField.autocorrectionType = FALSE; // or use  UITextAutocorrectionTypeNo
    textField.autocapitalizationType = UITextAutocapitalizationTypeNone;

}

Swift

func textFieldDidBeginEditing(textfield : UITextField)
{
    textField.autocorrectionType = .No
    textField.autocapitalizationType = .None
    textField.spellCheckingType = .No
}

Swift3

  func textFieldDidBeginEditing(_ textField : UITextField)
{
    textField.autocorrectionType = .no
    textField.autocapitalizationType = .none
    textField.spellCheckingType = .no
}

You're setting autocorrectionType to FALSE as if it were a BOOL, but it actually has type UITextAutocorrectionType. So FALSE is being interpreted as UITextAutocorrectionTypeDefault, which means that autocorrection is probably enabled.

I bet it found the name "Phil" in your address book and is autocorrecting the capitalization to match.