（转）解决NSMutableAttributedString富文本,不同文字大小水平轴对齐问题(默认底部对齐)

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默认是底部对齐,其实对的也不齐,

目标效果: 

代码:

NSBaselineOffsetAttributeName

基线偏移量: 
调整: NSBaselineOffsetAttributeName的值得大小,就可以得到不同的对齐位置

CGFloat fontRatio = 0.16;//基线偏移比率

CGFloat fontRatio = 0.66;//基线偏移比率

- (void)viewDidLoad { [super viewDidLoad]; self.title = @"富文本"; NSString *text = @"(2) 3 : 2 (1)"; NSInteger fontSize1 = 30; NSInteger fontSize2 = 16; CGFloat fontRatio = 0.66;//基线偏移比率 UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(150, 200, 150, 40)]; label.text = text; NSMutableAttributedString *attributedStringM = [[NSMutableAttributedString alloc] initWithString:text]; [attributedStringM addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:fontSize2] range:NSMakeRange(0, 3)]; [attributedStringM addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(0, 3)]; [attributedStringM addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:fontSize1] range:NSMakeRange(3, text.length - 6)]; [attributedStringM addAttribute:NSForegroundColorAttributeName value:[UIColor blueColor] range:NSMakeRange(3, text.length - 6)]; [attributedStringM addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:fontSize2] range:NSMakeRange(text.length - 3, 3)]; [attributedStringM addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(text.length - 3, 3)]; //不同大小的文字水平中部对齐(默认是底部对齐) [attributedStringM addAttribute:NSBaselineOffsetAttributeName value:@(fontRatio * (fontSize1 - fontSize2)) range:NSMakeRange(0, 3)]; [attributedStringM addAttribute:NSBaselineOffsetAttributeName value:@(fontRatio * (fontSize1 - fontSize2)) range:NSMakeRange(text.length - 3, 3)]; label.attributedText = attributedStringM; [self.view addSubview:label]; }