Extensions.swift

extension String
{
  func width(withConstrainedHeight height: CGFloat, font: UIFont) -> CGFloat
  {
    let constraintRect = CGSize(width: .greatestFiniteMagnitude, height: height);

    let boundingBox = self.boundingRect(with: constraintRect, options: .usesLineFragmentOrigin, attributes: [NSFontAttributeName: font], context: nil)

    return boundingBox.width;
  }
}