iOS 读取文件中的内存大小

- (void)getCacheSize
{
    // 总大小
    unsigned long long size = 0;
    
    // 获得缓存文件夹路径
    NSString *cachesPath = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES).lastObject;
    NSString *dirpath = [cachesPath stringByAppendingPathComponent:@"MP3/Abc"];
    
    // 文件管理者
    NSFileManager *mgr = [NSFileManager defaultManager];
    
    // 获得文件夹的大小  == 获得文件夹中所有文件的总大小
//    XMGLog(@"contents - %@", [mgr contentsOfDirectoryAtPath:dirpath error:nil]);
    NSArray *subpaths = [mgr subpathsAtPath:dirpath];
    for (NSString *subpath in subpaths) {
        // 全路径
        NSString *fullSubpath = [dirpath stringByAppendingPathComponent:subpath];
        // 累加文件大小
        size += [mgr attributesOfItemAtPath:fullSubpath error:nil].fileSize;
        
//        NSDictionary *attrs = [mgr attributesOfItemAtPath:fullSubpath error:nil];
//        size += [attrs[NSFileSize] unsignedIntegerValue];
    }
    
    XMGLog(@"%zd", size);
}