相关疑难解决方法(0)

我试图阻止整个文件夹由itunes支持.我按照技术报告http://developer.apple.com/library/ios/#qa/qa1719/_index.html但似乎falg每次都是零.我在模拟器和设备上使用IOS 5.1.但没有任何帮助.这些方法每次都会返回"成功",但标志仍为零.

+ (BOOL) hasSkipBackupAttributeToItemAtURL:(NSURL *)URL
{
    NSError *error = nil;

    id flag = nil;
    BOOL success = [URL getResourceValue: &flag
                                  forKey: NSURLIsExcludedFromBackupKey error: &error];

    if(!success){

        NSLog(@"Error excluding %@ from backup %@", [URL lastPathComponent], error);
        return false;
    }

    if (!flag)
        return false;

    return [flag boolValue];
}

+ (BOOL)addSkipBackupAttributeToItemAtURL:(NSURL *)URL
{
    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 …