NSMutableAttributedString 设置不同颜色，不同字体的String

   UILabel *infoLabel = [[UILabel alloc]initWithFrame:CGRectMake(95, 20, 190, 70)];

    infoLabel.backgroundColor = [UIColor clearColor];

    infoLabel.textAlignment = NSTextAlignmentLeft;

    infoLabel.font = [UIFont systemFontOfSize:13];

    infoLabel.numberOfLines = 0;

    infoLabel.textColor = KSignTextColor;

    NSString *infoString = @"连续签到1天得10积分；\n连续签到2天得15积分；\n连续签到3天及以上得20积分；\n注：若连续签到终端则重新计算";

    NSRange infoRange = [infoString rangeOfString:@"注："];

    NSMutableAttributedString  *infoATString = [[NSMutableAttributedString alloc]initWithString:infoString ];

    [infoATString addAttribute:NSForegroundColorAttributeName

                        value:[UIColor redColor]

                        range:infoRange];

   // NSRange range = NSMakeRange(infoString.length-1, 1);

    //[infoATString addAttribute:(NSString *)kCTFontAttributeName value:(id)[UIFont systemFontOfSize:10] range:range];

    [infoLabel setAttributedText:infoATString];