iOS NSMutableAttributedString修改UILabel的部分字体、颜色等属性

NSMutableAttributedString可以修改UILabel的部分文字的颜色、字体等，也可以在UILabel里添加image展示。
1.改变颜色 range是需要修改颜色的文字范围

+ (NSMutableAttributedString *)changeColorWithColor:(UIColor *)color content:(NSString *)content range:(NSRange)range {
    NSMutableAttributedString *attributedStr = [[NSMutableAttributedString alloc]initWithString:content];
    [attributedStr addAttribute:NSForegroundColorAttributeName
                          value:color
                          range:range];
    return attributedStr;
}

2.修改字体

+ (NSMutableAttributedString *)changeFontWithFont:(UIFont *)font content:(NSString *)content range:(NSRange)range {
    NSMutableAttributedString *attributedStr = [[NSMutableAttributedString alloc]initWithString:content];
    [attributedStr addAttribute:NSFontAttributeName value:font range:range];
    return attributedStr;
}

3.UILabel里展示本地图片

+ (NSMutableAttributedString *)addLocalImageInsertTextWithImageName:(NSString *)imageName mutableAttributeString:(NSMutableAttributedString *)mutableAttributeString index:(NSInteger)index imageWidth:(CGFloat)imageWidth imageHeight:(CGFloat)imageHeight{
    UIImage *image = [UIImage imageNamed:imageName];
    NSTextAttachment *attch = [[NSTextAttachment alloc] init];
    attch.image = image;
    attch.bounds = CGRectMake(0, -3, imageWidth, imageHeight);
    NSAttributedString *string = [NSAttributedString attributedStringWithAttachment:attch];
    [mutableAttributeString insertAttributedString:string atIndex:index];
    return mutableAttributeString;
}

4.设置UILabel行间距

+ (NSMutableAttributedString *)lineSpacingWithAttributedString:(NSMutableAttributedString *)str lineSpacing:(CGFloat)lineSpacing content:(NSString *)content {
    NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
    [str addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, content.length)];
    [paragraphStyle setLineSpacing:lineSpacing];//调整行间距
    return str;
}