-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    NSString *url = self.dataArray[indexPath.row];
    /**
     *  参数1:图片URL
     *  参数2:imageView 宽度
     *  参数3:预估高度(此高度仅在图片尚未加载出来前起作用,不影响真实高度)
     */
    return [XHWebImageAutoSize imageHeightForURL:[NSURL URLWithString:url] layoutWidth:[UIScreen mainScreen].bounds.size.width-16 estimateHeight:200];
}   

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    DemoVC1Cell *cell = [tableView dequeueReusableCellWithIdentifier:cellId];
    if(!cell)
    {
        cell = [[DemoVC1Cell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellId];
    }
    NSString *url = self.dataArray[indexPath.row];
    //加载网络图片使用SDWebImage
    [cell.imgView sd_setImageWithURL:[NSURL URLWithString:url] completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL) {
        
        /**
         *  缓存image size
         */
        [XHWebImageAutoSize storeImageSize:image forURL:imageURL completed:^(BOOL result) {
            
           /**
            *  尺寸缓存成功,reload cell
            */
            if(result)  [tableView  xh_reloadRowAtIndexPath:indexPath forURL:imageURL];
            
        }];
        
    }];
    return cell;
}

/**
 *   Get image height
 *
 *  @param url            imageURL
 *  @param layoutWidth    layoutWidth
 *  @param estimateHeight estimateHeight(default 100)
 *
 *  @return imageHeight
 */
+(CGFloat)imageHeightForURL:(NSURL *)url layoutWidth:(CGFloat)layoutWidth estimateHeight:(CGFloat )estimateHeight;

/**
 *  Get image size from cache,query the disk cache synchronously after checking the memory cache
 *
 *  @param url imageURL
 *
 *  @return imageSize
 */
+(CGSize )imageSizeFromCacheForURL:(NSURL *)url;

/**
 *  Store an imageSize into memory and disk cache
 *
 *  @param image          image
 *  @param url            imageURL
 *  @param completedBlock An block that should be executed after the imageSize has been saved (optional)
 */
+(void)storeImageSize:(UIImage *)image forURL:(NSURL *)url completed:(XHWebImageAutoSizeCacheCompletionBlock)completedBlock;

/**
 *  Get reload state from cache,query the disk cache synchronously after checking the memory cache
 *
 *  @param url imageURL
 *
 *  @return reloadState
 */
+(BOOL)reloadStateFromCacheForURL:(NSURL *)url;

/**
 *  Store an reloadState into memory and disk cache
 *
 *  @param state          reloadState
 *  @param url            imageURL
 *  @param completedBlock An block that should be executed after the reloadState has been saved (optional)
 */
+(void)storeReloadState:(BOOL)state forURL:(NSURL *)url completed:(XHWebImageAutoSizeCacheCompletionBlock)completedBlock;

/**
 *  Reload row
 *
 *  @param indexPath indexPath
 *  @param url        imageURL
 */
-(void)xh_reloadRowAtIndexPath:(NSIndexPath *)indexPath forURL:(NSURL *)url;

/**
 *  Reload row withRowAnimation
 *
 *  @param indexPath indexPath
 *  @param animation UITableViewRowAnimation
 *  @param url       imageURL
 */
-(void)xh_reloadRowAtIndexPath:(NSIndexPath *)indexPath withRowAnimation:(UITableViewRowAnimation)animation forURL:(NSURL *)url;

/**
 *  Reload item
 *
 *  @param indexPath indexPath
 *  @param url        imageURL
 */
-(void)xh_reloadItemAtIndexPath:(NSIndexPath *)indexPath forURL:(NSURL *)url;