回收钢铁的答案的Swift版本+ intrinsizeContentSize()。

它支持一个更传统的设置insets为其他视图对象的insets，同时能够设置insets在接口生成器，即insets设置像这样编程:

label.insets = UIEdgeInsetsMake(0, 0, 5, 0)

如果有任何错误，请告诉我。

斯威夫特5

@IBInspectable var topInset: CGFloat = 0.0
@IBInspectable var leftInset: CGFloat = 0.0
@IBInspectable var bottomInset: CGFloat = 0.0
@IBInspectable var rightInset: CGFloat = 0.0

var insets: UIEdgeInsets {
    get {
        return UIEdgeInsets(top: topInset, left: leftInset, bottom: bottomInset, right: rightInset)
    }
    set {
        topInset = newValue.top
        leftInset = newValue.left
        bottomInset = newValue.bottom
        rightInset = newValue.right
    }
}

override func drawText(in rect: CGRect) {
    super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
}

override func sizeThatFits(_ size: CGSize) -> CGSize {
    var adjSize = super.sizeThatFits(size)
    adjSize.width += leftInset + rightInset
    adjSize.height += topInset + bottomInset
    
    return adjSize
}

override var intrinsicContentSize: CGSize {
    var contentSize = super.intrinsicContentSize
    contentSize.width += leftInset + rightInset
    contentSize.height += topInset + bottomInset
    
    return contentSize
}

斯威夫特4.2

@IBDesignable class InsetLabel: UILabel {
    @IBInspectable var topInset: CGFloat = 0.0
    @IBInspectable var leftInset: CGFloat = 0.0
    @IBInspectable var bottomInset: CGFloat = 0.0
    @IBInspectable var rightInset: CGFloat = 0.0
    
    var insets: UIEdgeInsets {
        get {
            return UIEdgeInsetsMake(topInset, leftInset, bottomInset, rightInset)
        }
        set {
            topInset = newValue.top
            leftInset = newValue.left
            bottomInset = newValue.bottom
            rightInset = newValue.right
        }
    }
    
    override func drawText(in rect: CGRect) {
        super.drawText(in: rect.inset(by: insets))
    }
    
    override func sizeThatFits(_ size: CGSize) -> CGSize {
        var adjSize = super.sizeThatFits(size)
        adjSize.width += leftInset + rightInset
        adjSize.height += topInset + bottomInset
        
        return adjSize
    }
    
    override var intrinsicContentSize: CGSize {
        var contentSize = super.intrinsicContentSize
        contentSize.width += leftInset + rightInset
        contentSize.height += topInset + bottomInset
        
        return contentSize
    }
}

斯威夫特3

@IBDesignable class InsetLabel: UILabel {
    @IBInspectable var topInset: CGFloat = 0.0
    @IBInspectable var leftInset: CGFloat = 0.0
    @IBInspectable var bottomInset: CGFloat = 0.0
    @IBInspectable var rightInset: CGFloat = 0.0
    
    var insets: UIEdgeInsets {
        get {
            return UIEdgeInsetsMake(topInset, leftInset, bottomInset, rightInset)
        }
        set {
            topInset = newValue.top
            leftInset = newValue.left
            bottomInset = newValue.bottom
            rightInset = newValue.right
        }
    }
    
    override func drawText(in rect: CGRect) {
        super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
    }
    
    override func sizeThatFits(_ size: CGSize) -> CGSize {
        var adjSize = super.sizeThatFits(size)
        adjSize.width += leftInset + rightInset
        adjSize.height += topInset + bottomInset
        
        return adjSize
    }
    
    override var intrinsicContentSize: CGSize {
        var contentSize = super.intrinsicContentSize
        contentSize.width += leftInset + rightInset
        contentSize.height += topInset + bottomInset
        
        return contentSize
    }
}

斯威夫特2.2

@IBDesignable class InsetLabel: UILabel {
    @IBInspectable var topInset: CGFloat = 0.0
    @IBInspectable var leftInset: CGFloat = 0.0
    @IBInspectable var bottomInset: CGFloat = 0.0
    @IBInspectable var rightInset: CGFloat = 0.0
    
    var insets: UIEdgeInsets {
        get {
            return UIEdgeInsetsMake(topInset, leftInset, bottomInset, rightInset)
        }
        set {
            topInset = newValue.top
            leftInset = newValue.left
            bottomInset = newValue.bottom
            rightInset = newValue.right
        }
    }
        
    override func drawTextInRect(rect: CGRect) {
        super.drawTextInRect(UIEdgeInsetsInsetRect(rect, insets))
    }
        
    override func sizeThatFits(size: CGSize) -> CGSize {
        var adjSize = super.sizeThatFits(size)
        adjSize.width += leftInset + rightInset
        adjSize.height += topInset + bottomInset
        
        return adjSize
    }
    
    override func intrinsicContentSize() -> CGSize {
        var contentSize = super.intrinsicContentSize()
        contentSize.width += leftInset + rightInset
        contentSize.height += topInset + bottomInset
        
        return contentSize
    }
}

如果以编程方式创建标签，则可以使用sizeThatFits方法计算填充。如果使用多行，文本将以最大宽度值换行。

let text = UILabel()
let padding = 10
text.layer.cornerRadius = 5
text.layer.masksToBounds = true
text.text = "Hello"
text.font = UIFont(name: text.font.fontName, size: 18)
text.textAlignment = NSTextAlignment.center
text.numberOfLines = 1

let maxSize = CGSize(width: 100, height: 100)
var size = text.sizeThatFits(maxSize)
size.width = size.width + padding * 2
size.height = size.height + padding * 2
text.frame = CGRect(origin: CGPoint(x: 0, y: 0), size: size)

Swift 3 &自动布局兼容版本:

class InsetLabel: UILabel {

    var insets = UIEdgeInsets()

    convenience init(insets: UIEdgeInsets) {
        self.init(frame: CGRect.zero)
        self.insets = insets
    }

    convenience init(dx: CGFloat, dy: CGFloat) {
        let insets = UIEdgeInsets(top: dy, left: dx, bottom: dy, right: dx)
        self.init(insets: insets)
    }

    override func drawText(in rect: CGRect) {
        super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
    }

    override var intrinsicContentSize: CGSize  {
        var size = super.intrinsicContentSize
        size.width += insets.left + insets.right
        size.height += insets.top + insets.bottom
        return size
    }
}

也许过会儿再去派对，但下面的就行了。只是UILabel的子类。

#import "UITagLabel.h"

#define padding UIEdgeInsetsMake(5, 10, 5, 10)

@implementation UITagLabel

- (void)drawTextInRect:(CGRect)rect {
    [super drawTextInRect:UIEdgeInsetsInsetRect(rect, padding)];
}

- (CGSize) intrinsicContentSize {
    CGSize superContentSize = [super intrinsicContentSize];
    CGFloat width = superContentSize.width + padding.left + padding.right;
    CGFloat height = superContentSize.height + padding.top + padding.bottom;
    return CGSizeMake(width, height);
}

- (CGSize) sizeThatFits:(CGSize)size {
    CGSize superSizeThatFits = [super sizeThatFits:size];
    CGFloat width = superSizeThatFits.width + padding.left + padding.right;
    CGFloat height = superSizeThatFits.height + padding.top + padding.bottom;
    return CGSizeMake(width, height);
}

@end

对于Xamarin用户(使用统一API):

class UIMarginLabel : UILabel
{
    public UIMarginLabel()
    {
    }

    public UIMarginLabel( CGRect frame ) : base( frame )
    {
    }

    public UIEdgeInsets Insets { get; set; }

    public override void DrawText( CGRect rect )
    {
        base.DrawText( Insets.InsetRect( rect ) );
    }
}

对于那些使用原始MonoTouch API的人:

public class UIMarginLabel : UILabel
{
    public UIEdgeInsets Insets { get; set; }

    public UIMarginLabel() : base()
    {
        Insets = new UIEdgeInsets(0, 0, 0, 0);
    }
    public UIMarginLabel(RectangleF frame) : base(frame)
    {
        Insets = new UIEdgeInsets(0, 0, 0, 0);
    }

    public override void DrawText(RectangleF frame)
    {
        base.DrawText(new RectangleF(
            frame.X + Insets.Left,
            frame.Y + Insets.Top,
            frame.Width - Insets.Left - Insets.Right,
            frame.Height - Insets.Top - Insets.Bottom));
    }
}

blyabtroi的asnwer在Swift中转换(不需要子类化)

let style: NSMutableParagraphStyle = NSParagraphStyle.defaultParagraphStyle().mutableCopy() as! NSMutableParagraphStyle
style.alignment = .Justified
style.firstLineHeadIndent = 10.0
style.headIndent = 10.0
style.tailIndent = -10.0
let attrText: NSAttributedString = NSAttributedString(string: title, attributes: [NSParagraphStyleAttributeName:style])
let label: UILabel = UILabel(frame: someFrame)
label.numberOfLines = 0
label.attributedText = attrText