ios存储网络下载的大数据被appstore拒绝解决方案

今天起床，发现上周发布的app遭拒绝了。下面是resolution center的回复：

----- 2.23 -----
We found that your app does not follow the iOS Data Storage Guidelines, which is required per the App
Store Review Guidelines.
In particular, we found that on launch and/or content download, your app stores 79.27MB. To check how much data your app is storing:
- Install and launch your app
- Go to Settings > iCloud > Storage & Backup > Manage Storage
- If necessary, tap "Show all apps"
- Check your app's storage
The iOS Data Storage Guidelines indicate that only content that the user creates using your app, e.g., documents, new files, edits, etc., should be backed up by iCloud.
Temporary files used by your app should only be stored in the /tmp directory; please remember to delete the files stored in this location when the user exits the app.
Data that can be recreated but must persist for proper functioning of your app - or because customers expect it to be available for offline use - should be marked with the "do not back up" attribute. For NSURL objects, add the NSURLIsExcludedFromBackupKey
attribute to prevent the corresponding file from being backed up. For CFURLRef objects, use the corresponding kCFURLIsExcludedFromBackupKey attribute.
For more information, please see Technical Q&A 1719: How do I prevent files from being backed up to iCloud
and iTunes?.
It is necessary to revise your app to meet the requirements of the iOS Data Storage Guidelines.

- (BOOL)addSkipBackupAttributeToItemAtURL:(NSURL *)URL
{
assert([[NSFileManager defaultManager] fileExistsAtPath: [URL path]]);

NSError *error = nil;
BOOL success = [URL setResourceValue: [NSNumber numberWithBool: YES]
forKey: NSURLIsExcludedFromBackupKey error: &error];
if(!success){
NSLog(@"Error excluding %@ from backup %@", [URL lastPathComponent], error);
}
return success;
}