使用UILabel之attributeText属性，展示H5代码片段，实现富文本效果。

遇到问题:图片尺寸和屏幕尺寸不匹配，这就要求调整h5代码片段中图片标签中图片尺寸, 实现如下:

@implementation AttributeTools
/**
Filter H5字符串中的图片标签，自定义图片宽度。
@param width 宽度
@return result
*/
+(NSString *)pointSizeOfImageInHtml_Str:(NSString*)str Width:(CGFloat)width{
    if (str == nil || str.length == 0) { return @"";  }
    NSString *content = [str stringByReplacingOccurrencesOfString:@"&quot" withString:@"'"];
    content = [content stringByReplacingOccurrencesOfString:@"&lt;" withString:@"<"];
    content = [content stringByReplacingOccurrencesOfString:@"&gt;" withString:@">"];
    content = [content stringByReplacingOccurrencesOfString:@"&quot;" withString:@"\""];
    NSString *html = content;
    NSString * regExpStr = @"<(img|IMG)[^\\<\\>]*>";
    NSRegularExpression *regex=[NSRegularExpression regularExpressionWithPattern:regExpStr options:NSRegularExpressionCaseInsensitive error:nil];
    NSArray *matches=[regex matchesInString:html
                                    options:0
                                      range:NSMakeRange(0, [html length])];
    //H5中<img ...... />标签数组
    NSMutableArray *imgArray = [NSMutableArray array];
    NSMutableArray *urlArray = [NSMutableArray array];
    for (NSTextCheckingResult *result in matches) {
        NSRange range   = result.range;
        NSString *group = [html substringWithRange:range];
        NSRange srange1 = [group rangeOfString:@"http"];
        NSString *tempString1 = [group substringWithRange:NSMakeRange(srange1.location, group.length - srange1.location)];
        NSRange srange2 = [tempString1 rangeOfString:@"\""];
        NSString *tempString2 = [tempString1 substringWithRange:NSMakeRange(0,srange2.location)];
        [urlArray addObject:tempString2];
        [imgArray addObject:group];
    }
    for (int i = 0; i < imgArray.count; i++) {
        NSString *string = imgArray[i];
        html = [html stringByReplacingOccurrencesOfString:string withString:[NSString stringWithFormat:@"<img src=\"%@\" title=\"\" alt=\"%ld\" width=\"%f\" height=\"auto\">",urlArray[i],[self getNowTimeTimestamp]+i,width]];
    }
    return html;
}
+(long)getNowTimeTimestamp{
    NSDate *datenow = [NSDate date];
    return (long)[datenow timeIntervalSince1970];
}
@end