c# - 一个大数组如何拆分成更小的数组？

Question

给定一个大数组，如何将其拆分为较小的数组，并将较小数组的大小指定为方法的参数？

例如，给定数字，Split 的实现方式是什么？

int[] numbers = new int[7845];

int[][] sectionedNumbers = numbers.Split(1000);

sectionedNumbers.Length; //outputs 8
sectionedNumbers[7].Length; //outputs 845

Answer 1

您可以使用扩展方法来实现:

using System;

static class Program
{
    static T[][] Split<T>(this T[] arrayIn, int length)
    {
        bool even = arrayIn.Length%length == 0;
        int totalLength = arrayIn.Length/length;
        if (!even)
            totalLength++;

        T[][] newArray = new T[totalLength][];
        for (int i = 0; i < totalLength;++i )
        {
            int allocLength = length;
            if (!even && i == totalLength - 1)
                allocLength = arrayIn.Length % length;

            newArray[i] = new T[allocLength];
            Array.Copy(arrayIn, i * length, newArray[i], 0, allocLength);
        }
        return newArray;
    }

    static void Main(string[] args)
    {
        int[] numbers = new int[8010];
        for (int i = 0; i < numbers.Length; ++i)
            numbers[i] = i;

        int[][] sectionedNumbers = numbers.Split(1000);

        Console.WriteLine("{0}", sectionedNumbers.Length);
        Console.WriteLine("{0}", sectionedNumbers[7].Length);
        Console.WriteLine("{0}", sectionedNumbers[1][0]);
        Console.WriteLine("{0}", sectionedNumbers[7][298]);
        Console.ReadKey();
    } 
}

这打印:

9
1000
1000
7298