程序代码：

using System;
using System.Collections.Generic;
using System.Text;

namespace ArrRev
{
    public static class Arr_Rev//假如不存在逆矩阵，将数组清空为0。高手注意数组是引用，dll返回的是逆矩阵，原来的数据被覆盖了！为了简单起见，请先将矩阵从左到右，从上到下转换成一维的数组

    {
        private static double Mul_TWO(params double[] m) //二阶行列式的值
        {
            double Result = m[0] * m[3] - m[1] * m[2];
           
            return Result;
        }

        private static double Mul_THREE(params double[] m) //三阶行列式的值
        {
            double temp1 = m[0] * Mul_TWO(m[4], m[5], m[7], m[8]);
            double temp2 = m[1] * Mul_TWO(m[3], m[5], m[6], m[8]);
            double temp3 = m[2] * Mul_TWO(m[3], m[4], m[6], m[7]);

            double Result = temp1 + temp3 - temp2;

            return Result;
        }

        public static void Rev_TWO(double[] Arr) //求二维矩阵的逆
        {
            double Result = Arr[0] * Arr[3] - Arr[1] * Arr[2];
           
            if (Result != 0)
            {
                double Num1=Arr[0];
                double Num2=Arr[1];
                double Num3=Arr[2];
                double Num4=Arr[3];

           
                Arr[0] = Num4 / Result;
                Arr[1] = -Num2 / Result; //求伴随矩阵
                Arr[2] = -Num3 / Result;
                Arr[3] = Num1 / Result;
            }
            else
            {
                for (int i = 0; i < 4; i++)
                    Arr[i] = 0;
            }
        }

        public static void Rev_THREE(double[] Arr) //求三维矩阵的逆
         {
            double Result = Mul_Three(Arr);

            if (Result != 0)
            {
                double[] m = new double[9];

                m[0] = Mul_TWO(Arr[4], Arr[5], Arr[7], Arr[8]); //求伴随矩阵
                m[1] = -Mul_TWO(Arr[1], Arr[2], Arr[7], Arr[8]);
                m[2] = Mul_TWO(Arr[1], Arr[2], Arr[4], Arr[5]);
                m[3] = -Mul_TWO(Arr[3], Arr[5], Arr[6], Arr[8]);
                m[4] = Mul_TWO(Arr[0], Arr[2], Arr[6], Arr[8]);
                m[5] = -Mul_TWO(Arr[0], Arr[2], Arr[3], Arr[5]);
                m[6] = Mul_TWO(Arr[3], Arr[4], Arr[6], Arr[7]);
                m[7] = -Mul_TWO(Arr[0], Arr[1], Arr[6], Arr[7]);
                m[8] = Mul_TWO(Arr[0], Arr[1], Arr[3], Arr[4]);

                for (int i = 0; i < 9; i++)
                {
                    Arr[i] = m[i] / Result;
                }
            }
            else
            {
                for (int i = 0; i < 9; i++)
                {
                    Arr[i] = 0;
                }
            }
        }
    }
}