对于多行文本，可以使用NSAttributedString设置左右边距。

NSMutableParagraphStyle *style =  [[NSParagraphStyle defaultParagraphStyle] mutableCopy];
style.alignment = NSTextAlignmentJustified;
style.firstLineHeadIndent = 10.0f;
style.headIndent = 10.0f;
style.tailIndent = -10.0f;   

NSAttributedString *attrText = [[NSAttributedString alloc] initWithString:title attributes:@{ NSParagraphStyleAttributeName : style}];  

UILabel * label = [[UILabel alloc] initWithFrame:someFrame];
label.numberOfLines = 0;
label.attributedText = attrText;

以下是Swift 5采用的上述示例:

extension UILabel {
    func setMargins(margin: CGFloat = 10) {
        if let textString = self.text {
            var 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
        }
    }
}

我认为UILabel类没有设置边距的方法。为什么不把标签的位置设置在需要的位置?

见下面的代码:

UILabel *label = [[UILabel alloc] init];
label.text = @"This is label";
label.frame = CGRectMake(0,0,100,100);

如果来自接口构建器，则按以下方式定位Label:

yourLabel.frame = CGRectMake(0,0,100,100);

#import "E_LabelWithPadding.h"
#define padding UIEdgeInsetsMake(2, 0, 2, 0)
#define padding1 UIEdgeInsetsMake(0, 0, 0, 0)
@implementation E_LabelWithPadding
- (void)drawTextInRect:(CGRect)rect {
if (![self.text isEqualToString:@""]) {
    [super drawTextInRect:UIEdgeInsetsInsetRect(rect, padding)];
}else {
    [super drawTextInRect:UIEdgeInsetsInsetRect(rect, padding1)];
}

}

- (CGSize) intrinsicContentSize {
if (![self.text isEqualToString:@""]) {
    CGSize superContentSize = [super intrinsicContentSize];
    CGFloat width = superContentSize.width + padding.left + padding.right;
    CGFloat height = superContentSize.height + padding.top + padding.bottom;
    return CGSizeMake(width, height);
}else {
    CGSize superContentSize = [super intrinsicContentSize];
    CGFloat width = superContentSize.width + padding1.left + padding1.right;
    CGFloat height = superContentSize.height + padding1.top + padding1.bottom;
    return CGSizeMake(width, height);
}

}

- (CGSize) sizeThatFits:(CGSize)size {
if (![self.text isEqualToString:@""]) {
    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);
}else {
    CGSize superSizeThatFits = [super sizeThatFits:size];
    CGFloat width = superSizeThatFits.width + padding1.left + padding1.right;
    CGFloat height = superSizeThatFits.height + padding1.top + padding1.bottom;
    return CGSizeMake(width, height);
}

}

@end

对于这样一个简单的情况，子类化有点麻烦。另一种方法是将没有背景设置的UILabel添加到有背景设置的UIView中。将标签的x设置为10，并使外部视图的大小比标签宽20个像素。

我已经用xcode构建器解决了它(但肯定这可以通过swift使用约束来实现):

只需要创建一个相应大小的UIView 并添加一个UILabel类型的子视图

好了，你有填充了:)

为了消除单行标签的垂直填充，我做了:

// I have a category method setFrameHeight; you'll likely need to modify the frame.
[label setFrameHeight:font.pointSize];

或者，不带类别，使用:

CGRect frame = label.frame;
frame.size.height = font.pointSize;
label.frame = frame;