简单填充(Swift 3.0, Alvin George回答):

  class NewLabel: UILabel {

        override func textRect(forBounds bounds: CGRect, limitedToNumberOfLines numberOfLines: Int) -> CGRect {
                return self.bounds.insetBy(dx: CGFloat(15.0), dy: CGFloat(15.0))
        }

        override func draw(_ rect: CGRect) {
                super.drawText(in: self.bounds.insetBy(dx: CGFloat(5.0), dy: CGFloat(5.0)))
        }

  }

Swift 3代码及其实现示例

class UIMarginLabel: UILabel {

    var topInset:       CGFloat = 0
    var rightInset:     CGFloat = 0
    var bottomInset:    CGFloat = 0
    var leftInset:      CGFloat = 0

    override func drawText(in rect: CGRect) {
        let insets: UIEdgeInsets = UIEdgeInsets(top: self.topInset, left: self.leftInset, bottom: self.bottomInset, right: self.rightInset)
        self.setNeedsLayout()
        return super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
    }
}

class LabelVC: UIViewController {

    //Outlets
    @IBOutlet weak var labelWithMargin: UIMarginLabel!

    override func viewDidLoad() {
        super.viewDidLoad()

        //Label settings.
        labelWithMargin.leftInset = 10
        view.layoutIfNeeded()
    }
}

不要忘记在故事板标签对象中添加类名UIMarginLabel。 编码快乐!

如果在应用填充时遇到文本修剪问题，请使用此代码。

@IBDesignable class PaddingLabel: UILabel {

    @IBInspectable var topInset: CGFloat = 5.0
    @IBInspectable var bottomInset: CGFloat = 5.0
    @IBInspectable var leftInset: CGFloat = 5.0
    @IBInspectable var rightInset: CGFloat = 5.0

    override func drawText(in rect: CGRect) {
        let insets = UIEdgeInsets.init(top: topInset, left: leftInset, bottom: bottomInset, right: rightInset)
        super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
    }

    override var intrinsicContentSize: CGSize {
        var intrinsicSuperViewContentSize = super.intrinsicContentSize
        let textWidth = frame.size.width - (self.leftInset + self.rightInset)
        let newSize = self.text!.boundingRect(with: CGSize(textWidth, CGFloat.greatestFiniteMagnitude), options: NSStringDrawingOptions.usesLineFragmentOrigin, attributes: [NSFontAttributeName: self.font], context: nil)
        intrinsicSuperViewContentSize.height = ceil(newSize.size.height) + self.topInset + self.bottomInset
        return intrinsicSuperViewContentSize
    }
}

extension CGSize{
    init(_ width:CGFloat,_ height:CGFloat) {
        self.init(width:width,height:height)
    }
}

简单填充(Swift 3.0, Alvin George回答):

  class NewLabel: UILabel {

        override func textRect(forBounds bounds: CGRect, limitedToNumberOfLines numberOfLines: Int) -> CGRect {
                return self.bounds.insetBy(dx: CGFloat(15.0), dy: CGFloat(15.0))
        }

        override func draw(_ rect: CGRect) {
                super.drawText(in: self.bounds.insetBy(dx: CGFloat(5.0), dy: CGFloat(5.0)))
        }

  }

使用UILabel扩展的Swift 5示例

使用下面的代码，设置你的边距就像label. setmargin(15)一样简单。

extension UILabel {
    func setMargins(_ margin: CGFloat = 10) {
        if let textString = self.text {
            let paragraphStyle = NSMutableParagraphStyle()
            paragraphStyle.firstLineHeadIndent = margin
            paragraphStyle.headIndent = margin
            paragraphStyle.tailIndent = -margin
            let attributedString = NSMutableAttributedString(string: textString)
            attributedString.addAttribute(.paragraphStyle, value: paragraphStyle, range: NSRange(location: 0, length: attributedString.length))
            attributedText = attributedString
        }
    }
}

斯威夫特4

易于使用的解决方案，可用于项目中的所有UILabel子。

例子:

let label = UILabel()
    label.<Do something>
    label.padding = UIEdgeInsets(top: 0, left: 16, bottom: 0, right: 0)

UILabel扩展

import UIKit

extension UILabel {
    private struct AssociatedKeys {
        static var padding = UIEdgeInsets()
    }

    public var padding: UIEdgeInsets? {
        get {
            return objc_getAssociatedObject(self, &AssociatedKeys.padding) as? UIEdgeInsets
        }
        set {
            if let newValue = newValue {
                objc_setAssociatedObject(self, &AssociatedKeys.padding, newValue as UIEdgeInsets?, objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
            }
        }
    }

    override open func draw(_ rect: CGRect) {
        if let insets = padding {
            self.drawText(in: rect.inset(by: insets))
        } else {
            self.drawText(in: rect)
        }
    }

    override open var intrinsicContentSize: CGSize {
        guard let text = self.text else { return super.intrinsicContentSize }

        var contentSize = super.intrinsicContentSize
        var textWidth: CGFloat = frame.size.width
        var insetsHeight: CGFloat = 0.0
        var insetsWidth: CGFloat = 0.0

        if let insets = padding {
            insetsWidth += insets.left + insets.right
            insetsHeight += insets.top + insets.bottom
            textWidth -= insetsWidth
        }

        let newSize = text.boundingRect(with: CGSize(width: textWidth, height: CGFloat.greatestFiniteMagnitude),
                                        options: NSStringDrawingOptions.usesLineFragmentOrigin,
                                        attributes: [NSAttributedString.Key.font: self.font], context: nil)

        contentSize.height = ceil(newSize.size.height) + insetsHeight
        contentSize.width = ceil(newSize.size.width) + insetsWidth

        return contentSize
    }
}