获取iOS文件夹大小

    NSURL *cacheDirectory = [[NSFileManager defaultManager] URLForDirectory:NSCachesDirectory inDomain:NSUserDomainMaskappropriateForURL:nil create:NO error:nil];

    NSDictionary *attributes = [[NSFileManager defaultManager] attributesOfItemAtPath:cacheDirectory.path error:nil];

    NSNumber *sizeNumber = attributes[@"NSFileSize"];

    self.cacheDirectorySize.text = [NSStringstringWithFormat:@"%.1fM",sizeNumber.integerValue/1024.];