iOS 计算沙盒目录下一个文件夹的总大小

NSDirectoryEnumerator 枚举器

 nextObject返回nil值时，循环结束。这也是不能在数组中存储nil值的另一个原因：没办法判断nil是存储在数组中的数值还是代表循环结束的标志。

+ (long long)getFileSize{
    NSFileManager* fileManager=[NSFileManager defaultManager];
    NSDirectoryEnumerator * enumerator = [fileManager enumeratorAtPath:NSHomeDirectory()];
    long long totalSize = 0;
    NSString * aPath = @"";
    while (aPath = [enumerator nextObject]) {
        NSString * realPath = [NSHomeDirectory() stringByAppendingPathComponent:aPath];
        
        NSDictionary * dic = [fileManager attributesOfItemAtPath:realPath error:nil];
        totalSize += [dic[@"NSFileSize"] longLongValue];
    }
    NSLog(@"------- 总大小为:  %.2f",totalSize/1000.0/1000.0);
    totalSize = totalSize/1000.0/1000.0;
    
    return totalSize;
}