计算字符串得出结果

using System;
using System.Collections.Generic;
using System.Text;
using System.Linq.Expressions;
using System.Reflection;

namespace guess
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                Console.WriteLine(SetRandomVariable(GetTemplate()));
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }        

#if DEBUG
            Console.Read();
#endif


        }

        private static string GetTemplate()
        {

            StringBuilder stb = new StringBuilder();
            stb.AppendLine("Bangladesh - OneERP {0}hr");
            stb.AppendLine("CN - OneERP {1}hr");
            stb.AppendLine("Global - OneERP {2}hr");
            stb.AppendLine("FE - OneERP {3}hr");
            stb.AppendLine("UK - OneERP {4}hr");
            stb.AppendLine("Turkey - OneERP {5}hr");
            stb.AppendLine("Vietnam – OneERP {6}hr");
            stb.AppendLine("Singapore - OneERP {7}hr");
            stb.AppendLine("CN - HZ {8}hr");
            stb.AppendLine("Romania - OneERP {9}hr");
            stb.AppendLine("Thailand - OneERP {10}hr");
            stb.AppendLine("ZheJiang - OneERP {11}hr");
            stb.AppendLine("Global - OneERP SSO {12}hr");

            return stb.ToString();

        }

        private static string SetRandomVariable(string getTemplate)
        {

            int count = getTemplate.Split(‘\n‘).Length - 1;

            Random randomVariable = new Random(DateTime.Now.Millisecond);
            int max = 40;
          
            StringBuilder formula = new StringBuilder();
            object[] paramslist = new object[count];
            for (int i = 0; i < paramslist.Length; i++)
            {
                if (i == paramslist.Length - 1)
                {
                    paramslist[i] = max;
                    formula.Append(max);
                }
                else
                {
                    paramslist[i] = available(ref max, ref formula);
                }

            }

            //Com控件计算方法 需要目标平台X86 D找到引用的dll——属性——嵌入互操作类型——false
            MSScriptControl.ScriptControl sc = new MSScriptControl.ScriptControlClass();
            sc.Language = "JavaScript";
            Console.WriteLine("{0}={1}", formula.ToString(), sc.Eval(formula.ToString()).ToString());


            //DataTable().Compute计算方法
            Console.WriteLine("{0}={1}", formula.ToString(), new System.Data.DataTable().Compute(formula.ToString(), "").ToString());

            //另外有一种思路，把表达式作为一个sql发到数据库计算后结果再回传到程序。

            //lambda表达式树动态创建一个累加的表达式 需要.net FrameWork 4.5
            BinaryExpression binaryexpression = addExpression(count,null);
            Console.WriteLine(binaryexpression);
            LambdaExpression lambdaExpr = Expression.Lambda(binaryexpression, paramenterArray);
            Delegate de = lambdaExpr.Compile();
           // MethodInfo method = de.Method;
            Console.WriteLine(de.DynamicInvoke(paramslist));
            return string.Format(getTemplate, paramslist);
           
        }

        private static int available(ref int max, ref StringBuilder formula)
        {


            int temp = 0;
            if (max > 0)
            {
                Random randomVariable = new Random();
                if (max == 1)
                {
                    temp = randomVariable.Next(0, max + 1);
                }
                else
                {
                    temp = randomVariable.Next(0, max);
                }
                max = max - temp;
            }
            formula.AppendFormat("{0}+", temp);
            return temp;

        }
       static List<ParameterExpression>  paramenterArray=new List<ParameterExpression>() ;

        /// <summary>
        /// 
        /// </summary>
        /// <param name="lenght">累加次数</param>
        /// <param name="resultLeft">默认累加表达式</param>
        /// <returns></returns>
        private static BinaryExpression addExpression(int lenght, BinaryExpression resultLeft)
        {

            try
            {
                ParameterExpression left, right;
                left = Expression.Parameter(typeof(int), string.Format("left{0}", lenght) );
                right = Expression.Parameter(typeof(int), string.Format("right{0}", (lenght - 1)) );
                BinaryExpression result = Expression.Add(left, right);

                if (lenght > 2)
                {
                    paramenterArray.Add(left);
                    paramenterArray.Add(right);
                    if (resultLeft != null)
                        result = Expression.Add(resultLeft, addExpression(lenght - 2, result));
                    else
                        result = addExpression(lenght - 2, result);

                }
                if (lenght == 2)
                {
                    paramenterArray.Add(left);
                    paramenterArray.Add(right);
                    if (resultLeft != null)
                        result = Expression.Add(resultLeft, result);
                    else
                    {
                        //ignore;
                    }
                }
                if (lenght == 1)
                {
                    if (resultLeft != null)
                    {
                        ParameterExpression rExpression = Expression.Parameter(typeof(int), string.Format("right{0}", lenght ));
                        paramenterArray.Add(rExpression);
                        result = Expression.Add(resultLeft, rExpression);
                    }
                    else
                    {

                        throw (new Exception("当lenght等于1时，resultLeft参数不能为空"));
                    }
                }
                return result;
            }
            catch ( Exception ex)
            {
#if DEBUG
                Console.WriteLine(ex.StackTrace.ToString());
#endif
                throw (ex);
            }
        }
    }
}