很多答案都缺少对sizeThatFits的重写。有了这个子类，你可以创建标签，设置填充，然后输入label。sizetofit()，瞧。

import UIKit

class UILabelEx : UILabel
{
    var padding : UIEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)

    override func drawTextInRect(rect: CGRect) {

        super.drawTextInRect(UIEdgeInsetsInsetRect(rect, padding))
    }

    override func sizeThatFits(size: CGSize) -> CGSize
    {

        var adjSize = super.sizeThatFits(size)
        adjSize.width += padding.left + padding.right
        adjSize.height += padding.top + padding.bottom

        return adjSize
    }
}

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

没有子类和所有的爵士。我动态地做了这个:

[cell.textLabel setTranslatesAutoresizingMaskIntoConstraints:NO];
[cell.textLabel constraintTrailingEqualTo:cell.contentView constant:-100];

约束部分只是一个简单的代码糖纸(我们有相同的方法从上/下/左/右添加填充)..如果我在这里得到足够的爱，我将开放整个包装:

- (id)constraintTrailingEqualTo:(UIView *)toView constant:(CGFloat)constant
{
    NSLayoutConstraint *cn = [NSLayoutConstraint constraintWithItem:self
                                                          attribute:NSLayoutAttributeTrailing
                                                          relatedBy:NSLayoutRelationEqual
                                                             toItem:toView
                                                          attribute:NSLayoutAttributeTrailing
                                                         multiplier:1 constant:constant];

    [toView addConstraint:cn];
    return self;
}

(注意，我是在

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath: (NSIndexPath *)indexPath;

你可能需要调用[self setNeedsLayout];这取决于你的语境。

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)

要扩展Brody Robertson提供的答案，您可以添加IB可设计位。这意味着您可以在Storyboard中调整标签。

在你的子类UILabel做

#import <UIKit/UIKit.h>

IB_DESIGNABLE

@interface insetLabel : UILabel

@property (nonatomic, assign) IBInspectable CGFloat leftEdge;
@property (nonatomic, assign) IBInspectable CGFloat rightEdge;
@property (nonatomic, assign) IBInspectable CGFloat topEdge;
@property (nonatomic, assign) IBInspectable CGFloat bottomEdge;

@property (nonatomic, assign) UIEdgeInsets edgeInsets;

@end

然后做;

#import "insetLabel.h"

@implementation insetLabel

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self)
    {
        self.edgeInsets = UIEdgeInsetsMake(self.topEdge, self.leftEdge, self.bottomEdge, self.rightEdge);
    }
    return self;
}

- (void)drawTextInRect:(CGRect)rect
{
    self.edgeInsets = UIEdgeInsetsMake(self.topEdge, self.leftEdge, self.bottomEdge, self.rightEdge);

    [super drawTextInRect:UIEdgeInsetsInsetRect(rect, self.edgeInsets)];
}

- (CGSize)intrinsicContentSize
{
    CGSize size = [super intrinsicContentSize];
    size.width  += self.edgeInsets.left + self.edgeInsets.right;
    size.height += self.edgeInsets.top + self.edgeInsets.bottom;
    return size;
}

@end

EDIT

你应该为edgeInsets添加一个setter方法。

Swift 4版的blyabtroi解决方案

let leadingMargin: CGFloat = 10
let trailingMargin: CGFloat = 10

let style = NSMutableParagraphStyle()
style.alignment = .justified
style.firstLineHeadIndent = leadingMargin
style.headIndent = leadingMargin
style.tailIndent = trailingMargin

label.attributedText = NSAttributedString(string: "Label with margins", 
                                          attributes: [NSAttributedStringKey.paragraphStyle: style])