expression_tree.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Text;
using AgileObjects.ReadableExpressions;
using System.IO;
using System.Globalization;

namespace ConsoleApp3
{
    class Program
    {
        static void Testc()
        {
            ParameterExpression value = Expression.Parameter(typeof(int), "value");

            // Creating an expression to hold a local variable. 
            ParameterExpression result = Expression.Parameter(typeof(int), "result");

            // Creating a label to jump to from a loop.
            LabelTarget label = Expression.Label(typeof(int));

            // Creating a method body.
            BlockExpression block = Expression.Block(
                new[] { result },
                Expression.Assign(result, Expression.Constant(1)),
                    Expression.Loop(
                       Expression.IfThenElse(
                           Expression.GreaterThan(value, Expression.Constant(1)),
                           Expression.MultiplyAssign(result,
                               Expression.PostDecrementAssign(value)),
                           Expression.Break(label, result)
                       ),
                   label
                )
            );

            Console.WriteLine(block.ToReadableString());
            int factorial = Expression.Lambda<Func<int, int>>(block, value).Compile()(5);

            Console.WriteLine(factorial);
        }

        static IConvertible[] Read(BinaryReader reader, List<object[]> SubTables)
        {
            IConvertible[] result = new IConvertible[100];

            result[1] = reader.ReadInt32();
            result[2] = reader.ReadInt32();
            result[3] = reader.ReadInt32();

            var t1 = SubTables[1];
           // t1.
            for (int i = 0; i < result[5].ToInt32(CultureInfo.InvariantCulture); ++i)
            {
                t1[0] = reader.ReadInt32();

                for (int j = 0; j < result[5].ToInt32(CultureInfo.InvariantCulture); ++j)
                {
                    SubTables[3][0] = reader.ReadInt32();
                }
            }

            return result;
        }

        static void Main(string[] args)
        {
            Testc();
            Console.ReadLine();
            // Creating an expression to hold a local variable. 
            ParameterExpression result = Expression.Parameter(typeof(int[]), "result");

            // var array = new array[5];
            List<Expression> list = new List<Expression>();
            list.Add(Expression.Assign(result,
                    Expression.NewArrayBounds(typeof(int), Expression.Constant(5)))
                );

            for (int i = 0; i < 5; ++i)
            {
                // array[i] = i;
                var e = Expression.Assign(
                    Expression.ArrayAccess(result, Expression.Constant(i)),
                    Expression.Constant(i)
                    );
                
                list.Add(Expression.Assign(
                    Expression.ArrayAccess(result, Expression.Constant(i)),
                    Expression.Constant(i)
                    ));
            }

            {
                var eee = Expression.Variable(typeof(int), "var_int");
                Expression.Assign(eee,
                    Expression.Call(
                        Expression.Constant(args),
                        typeof(Expression).GetMethod("AddIntegers", new Type[] { typeof(int), typeof(int) }),
                        Expression.Constant(0))
                        );

                Expression.Assign(
                    Expression.ArrayAccess(result, Expression.Constant(10)),
                    eee);
            }

            var variable = list.OfType<ParameterExpression>().FirstOrDefault(v => v.Name == "var_");

            list.Add(result);

            var block = Expression.Block(new[] { result }, list);


            Console.WriteLine(block.ToReadableString());

           var a = Expression.Lambda<Func<int[]>>(block).Compile()();

            Console.WriteLine(a);

            Console.ReadLine();
        }

        static List<Expression> expressions = new List<Expression>();

        static void CreateReadType(ParameterExpression result, BinaryReader reader, int index, string name)
        {
            var variable = Expression.Variable(typeof(int), "var_"+ name);
            expressions.Add(variable);

            expressions.Add(
                Expression.Assign(variable,
                    Expression.Call(
                        Expression.Constant(reader),
                        typeof(BinaryReader).GetMethod("ReadInt32", new Type[] { typeof(int) }),
                        Expression.Constant(0)))
                        );

            expressions.Add(Expression.Assign(
                Expression.ArrayAccess(result, Expression.Constant(index)),
                variable)
                );
        }
    }
}