迭代的版本，其中包含元素的“组”(Version of iteration which takes “groups” of elements)

 我正在看一个旧的帮助器方法，我已经使用了一段时间来跟踪字节数组到输出。 我很久以前写过它并且它工作正常，但我想知道是否有更好的方法（少用代码）。 Linq浮现在我的脑海中，但我所拥有的解决方案非常低效。 我需要的是“foreach16”，或者一些枚举器，而不是一次返回1个元素，返回一组可枚举的元素。 除了我创建自己的枚举器类之外，还有内置的方法吗？ 
 
 以下示例提供了有关我要完成的更多信息。 
 
 原始代码 
 
    static void PrintBytes(byte[] bytes)
    {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < bytes.Length; i++)
        {
            if (i > 0 && ((i % 16) == 0))
            {
                // end of line, flushes bytes and resets buffer
                Console.WriteLine("   {0}", sb.ToString());
                sb.Length = 0;
            }
            else if (i > 0 && ((i % 8) == 0))
            {
                Console.Write(" ");
                sb.Append(' ');
            }

            Console.Write(" {0:X2}", (int)bytes[i]);
            if (' ' <= bytes[i] && bytes[i] <= '~')
            {
                sb.Append((char)bytes[i]);
            }
            else
            {
                // non-ASCII or control chars are printed as '.'
                sb.Append('.');
            }
        }

        // flushes the last few bytes
        if ((bytes.Length % 16) > 0)
        {
            // prints spaces where the missing bytes would be
            int spacesToPrint = 3 * (16 - (bytes.Length % 16));
            if ((bytes.Length % 16) <= 8)
            {
                spacesToPrint++;
            }

            Console.Write(new string(' ', spacesToPrint));
        }

        Console.WriteLine("   {0}", sb.ToString());
    }
 
 我现在拥有的 - 这就是我试图简化代码的原因。 但是我正在做很多Skip / Take，这会将代码的复杂性从线性增加到二次。 
 
    static void PrintBytesV2(byte[] bytes)
    {
        for (int i = 0; i < bytes.Length; i += 16)
        {
            PrintLineV2(bytes, i, Math.Min(16, bytes.Length - i));
        }
    }

    static void PrintLineV2(byte[] array, int offset, int count)
    {
        Console.Write(
            string.Join(
                " ", 
                array
                    .Skip(offset)
                    .Take(count)
                    .Select((b, i) =>
                        ((i == 8) ? " " : "") +
                            string.Format("{0:X2}", (int)b))));

        Console.Write( 
            new string(
                ' ', 
                (16 - count) * 3 +
                    (count <= 8 ? 1 : 0)) + 
            "  ");

        Console.WriteLine(
            string.Join(
            "", 
            array
                .Skip(offset)
                .Take(count)
                .Select(b => (' ' <= b && b <= '~') ? (char)b : '.')));
    }
 
 请注意，即使新代码是线性的，我也可能会坚持使用原始代码，因为1）它的工作原理; 2）我认为它更清晰。 但我不禁想知道是否有一些迭代群体的方法。 

I'm looking at an old helper method which I've been using for a while to trace byte arrays to the output. I wrote it a long time ago and it's been working fine, but I was wondering if there was a better way to do that (with less code). Linq came to my mind, but the solution which I have is awfully inefficient. What I'd need would be something along the lines of a "foreach16", or some enumerator which instead of returning 1 element at a time, returned a group of elements of an enumerable. Besides me creating my own enumerator class, is there a built-in way of doing that?
 
The examples below have more information on what I'm trying to accomplish.
 
Original code
 
    static void PrintBytes(byte[] bytes)
    {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < bytes.Length; i++)
        {
            if (i > 0 && ((i % 16) == 0))
            {
                // end of line, flushes bytes and resets buffer
                Console.WriteLine("   {0}", sb.ToString());
                sb.Length = 0;
            }
            else if (i > 0 && ((i % 8) == 0))
            {
                Console.Write(" ");
                sb.Append(' ');
            }

            Console.Write(" {0:X2}", (int)bytes[i]);
            if (' ' <= bytes[i] && bytes[i] <= '~')
            {
                sb.Append((char)bytes[i]);
            }
            else
            {
                // non-ASCII or control chars are printed as '.'
                sb.Append('.');
            }
        }

        // flushes the last few bytes
        if ((bytes.Length % 16) > 0)
        {
            // prints spaces where the missing bytes would be
            int spacesToPrint = 3 * (16 - (bytes.Length % 16));
            if ((bytes.Length % 16) <= 8)
            {
                spacesToPrint++;
            }

            Console.Write(new string(' ', spacesToPrint));
        }

        Console.WriteLine("   {0}", sb.ToString());
    }
 
What I have now - this is what I tried to simplify the code. But I'm doing many Skip/Take, which increases the complexity of the code from linear to quadratic.
 
    static void PrintBytesV2(byte[] bytes)
    {
        for (int i = 0; i < bytes.Length; i += 16)
        {
            PrintLineV2(bytes, i, Math.Min(16, bytes.Length - i));
        }
    }

    static void PrintLineV2(byte[] array, int offset, int count)
    {
        Console.Write(
            string.Join(
                " ", 
                array
                    .Skip(offset)
                    .Take(count)
                    .Select((b, i) =>
                        ((i == 8) ? " " : "") +
                            string.Format("{0:X2}", (int)b))));

        Console.Write( 
            new string(
                ' ', 
                (16 - count) * 3 +
                    (count <= 8 ? 1 : 0)) + 
            "  ");

        Console.WriteLine(
            string.Join(
            "", 
            array
                .Skip(offset)
                .Take(count)
                .Select(b => (' ' <= b && b <= '~') ? (char)b : '.')));
    }
 
Notice that even if the new code as it is were linear, I'd likely stick with the original code since 1) it works; and 2) I think it's more legible. But I can't help wondering whether there is some way of iterating over groups.

原文：https://stackoverflow.com/questions/10679245