SDWebImage-SDWebImageDownloader下载图片

[[SDWebImageDownloader sharedDownloader] downloadImageWithURL:[NSURL URLWithString:imgUrl] options:SDWebImageDownloaderHighPriority progress:nil completed:^(UIImage *image, NSData *data, NSError *error, BOOL finished) {                dispatch_async(dispatch_get_main_queue(), ^{                    if (wkself) {                        wkself.thumbImage = image;                    }                });            }];