SWIFT - UILabel content size for specific width

UILabel+Height.swift

//
//  UILabel+height.swift
//  AllBody
//
//  Created by Tiago Do Couto on 8/20/18.
//  Copyright © 2018 coutocode. All rights reserved.
//

import UIKit

extension UILabel {
    func textHeight(withWidth width: CGFloat) -> CGFloat {
        return text?.height(withWidth: width, font: font) ?? 0
    }
}

extension String {
    func height(withWidth width: CGFloat, font: UIFont) -> CGFloat {
        let maxSize = CGSize(width: width, height: CGFloat.greatestFiniteMagnitude)
        let contentSize = self.boundingRect(with: maxSize, options: [.usesLineFragmentOrigin], attributes: [.font : font], context: nil)
        return contentSize.height
    }
}