A Calculation Engine for .NET

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

namespace CalcEngine
{
#if DEBUG
    public partial class CalcEngine
    {
        public void Test()
        {
            // adjust culture
            var cultureInfo = this.CultureInfo;
            this.CultureInfo = System.Globalization.CultureInfo.InvariantCulture;

            // test internal operators
            Test("0", 0.0);
            Test("+1", 1.0);
            Test("-1", -1.0);
            Test("1+1", 1 + 1.0);
            Test("1*2*3*4*5*6*7*8*9", 1 * 2 * 3 * 4 * 5 * 6 * 7 * 8 * 9.0);
            Test("1/(1+1/(1+1/(1+1/(1+1/(1+1/(1+1/(1+1/(1+1/(1+1/(1+1))))))))))", 1 / (1 + 1 / (1 + 1 / (1 + 1 / (1 + 1 / (1 + 1 / (1 + 1 / (1 + 1 / (1 + 1 / (1 + 1 / (1 + 1.0)))))))))));
            Test("((1+2)*(2+3)/(4+5))^0.123", Math.Pow((1 + 2) * (2 + 3) / (4 + 5.0), 0.123));
            Test("10%", 0.1);
            Test("1e+3", 1000.0);

            // test simple variables
            Variables.Add("one", 1);
            Variables.Add("two", 2);
            Test("one + two", 3);
            Test("(two + two)^2", 16);
            Variables.Clear();

            // test DataContext
            var dc = DataContext;
            var p = Person.CreateTestPerson();
            DataContext = p;
            Test("Name", "Test Person");
            Test("Name.Length * 2", p.Name.Length * 2);
            Test("Children.Count", p.Children.Count);
            Test("Children(2).Name", p.Children[2].Name);
            Test("ChildrenDct(\"Test Child 2\").Name", p.ChildrenDct["Test Child 2"].Name);
            Test("ChildrenDct.Count", p.ChildrenDct.Count);
            DataContext = dc;

            // test functions
            Logical.Test(this);
            MathTrig.Test(this);
            Text.Test(this);
            Statistical.Test(this);

            // restore culture
            this.CultureInfo = cultureInfo;

        }
        public void Test(string expression, object expectedResult)
        {
            try
            {
                var result = Evaluate(expression);
                if (result is double && expectedResult is int)
                {
                    expectedResult = (double)(int)expectedResult;
                }
                if (!object.Equals(result, expectedResult))
                {
                    var msg = string.Format("error: {0} gives {1}, should give {2}", expression, result, expectedResult);
                    Debug.Assert(false, msg);
                }
            }
            catch (Exception x)
            {
                Debug.Assert(false, x.Message);
            }
        }
        public class Person
        {
            public Person()
            {
                Children = new List<Person>();
                ChildrenDct = new Dictionary<string, Person>();
            }
            public string Name { get; set; }
            public bool Male { get; set; }
            public DateTime Birth { get; set; }
            public List<Person> Children { get; private set; }
            public Dictionary<string, Person> ChildrenDct { get; private set; }
            public int Age { get { return DateTime.Today.Year - Birth.Year; } }

            public static Person CreateTestPerson()
            {
                var p = new Person();
                p.Name = "Test Person";
                p.Birth = DateTime.Today.AddYears(-30);
                p.Male = true;
                for (int i = 0; i < 5; i++)
                {
                    var c = new Person();
                    c.Name = "Test Child " + i.ToString();
                    c.Birth = DateTime.Today.AddYears(-i);
                    c.Male = i % 2 == 0;
                    p.Children.Add(c);
                    p.ChildrenDct.Add(c.Name, c);
                }
                return p;
            }
        }
    }
#endif
}