最简单的解决方案:

iOS 10及以上版本，Swift:

button.transform = CGAffineTransform(scaleX: -1.0, y: 1.0)
button.titleLabel?.transform = CGAffineTransform(scaleX: -1.0, y: 1.0)
button.imageView?.transform = CGAffineTransform(scaleX: -1.0, y: 1.0)

在iOS 10之前，Swift/Obj-C:

button.transform = CGAffineTransformMakeScale(-1.0, 1.0);
button.titleLabel.transform = CGAffineTransformMakeScale(-1.0, 1.0);
button.imageView.transform = CGAffineTransformMakeScale(-1.0, 1.0);

iOS 9及以上版本，Swift:(推荐)

button.semanticContentAttribute = .forceRightToLeft

当标题发生变化时，只需更新插图即可。你需要在另一侧用等量的、相反的插页来补偿插页。

[thebutton setTitle:title forState:UIControlStateNormal];
thebutton.titleEdgeInsets = UIEdgeInsetsMake(0, -thebutton.imageView.frame.size.width, 0, thebutton.imageView.frame.size.width);
thebutton.imageEdgeInsets = UIEdgeInsetsMake(0, thebutton.titleLabel.frame.size.width, 0, -thebutton.titleLabel.frame.size.width);

这里是解决方案的UIButton与中心对齐的内容。 这段代码使图像右对齐，并允许使用imageEdgeInsets和titleEdgeInsets进行宝贵的定位。

用你的自定义类子类化UIButton并添加:

- (CGRect)imageRectForContentRect:(CGRect)contentRect {
    CGRect frame = [super imageRectForContentRect:contentRect];
    CGFloat imageWidth = frame.size.width;
    CGRect titleRect = CGRectZero;
    titleRect.size = [[self titleForState:self.state] sizeWithAttributes:@{NSFontAttributeName: self.titleLabel.font}];
    titleRect.origin.x = (self.frame.size.width - (titleRect.size.width + imageWidth)) / 2.0 + self.titleEdgeInsets.left - self.titleEdgeInsets.right;
    frame.origin.x = titleRect.origin.x + titleRect.size.width - self.imageEdgeInsets.right + self.imageEdgeInsets.left;
    return frame;
}

- (CGRect)titleRectForContentRect:(CGRect)contentRect {
    CGFloat imageWidth = [self imageForState:self.state].size.width;
    CGRect frame = [super titleRectForContentRect:contentRect];
    frame.origin.x = (self.frame.size.width - (frame.size.width + imageWidth)) / 2.0 + self.titleEdgeInsets.left - self.titleEdgeInsets.right;
    return frame;
}

要在UIButton内右对齐图像，请尝试下面的代码

btn.contentHorizontalAlignment = .right

扩展UiButton并放入这些线条

    if let imageWidth = self.imageView?.frame.width {
        self.titleEdgeInsets = UIEdgeInsetsMake(0, -imageWidth, 0, imageWidth);
    }

    if let titleWidth = self.titleLabel?.frame.width {
        let spacing = titleWidth + 20
        self.imageEdgeInsets = UIEdgeInsetsMake(0, spacing, 0, -spacing);
    }

尽管一些建议的答案非常有创意和聪明，但最简单的解决方案如下:

button.semanticContentAttribute = UIApplication.shared
    .userInterfaceLayoutDirection == .rightToLeft ? .forceLeftToRight : .forceRightToLeft

就这么简单。作为奖励，在从右到左的区域中，图像将位于左侧。

编辑:这个问题已经被问过几次了，这是iOS 9 +。