using System;

using System.Linq.Expressions;

​

public class Model {

    public DateTime Date { get; set; }  

    public string FirstName {get; set; }

}

​

public enum MyEnum

{

Default = 0,

One = 1,

Two = 2,

}

public class Program

{

    public static void Main()

    {

        ParameterExpression param = Expression.Parameter(typeof(Model), "x");

        var property = Expression.Property(param, "Date");

        ConstantExpression constant = Expression.Constant(new DateTime(2015, 1, 1), typeof(DateTime));

        Expression finalExpression = Expression.LessThanOrEqual(property, constant);

        var utcNow = DateTime.UtcNow;

        Expression<Func<Model, string>> handMaidExpression = x => $"This is {x.FirstName} and an enum {MyEnum.Two} and {utcNow}";

        Console.WriteLine(handMaidExpression.Type);

        Console.WriteLine(handMaidExpression.Parameters[0]);

        Console.WriteLine(handMaidExpression.Body);

        var method = (MethodCallExpression)handMaidExpression.Body;

        Console.WriteLine(method.Method);       

        var arg0 = (ConstantExpression)method.Arguments[0];

        Console.WriteLine(arg0.Value);

        var arg1 = (MemberExpression)method.Arguments[1];

        Console.WriteLine(arg1.Member);

        Console.WriteLine(arg1.Expression.GetType());

        Console.WriteLine(arg1.Expression == handMaidExpression.Parameters[0]);

        var arg2 = (UnaryExpression)method.Arguments[2];

        var agr2Const = (ConstantExpression)arg2.Operand;

        Console.WriteLine(Convert.ToInt64(agr2Const.Value));

        Console.WriteLine(arg2.NodeType);

        var paramListExpr = Expression.Lambda<Func<object[]>>(Expression.NewArrayInit(typeof(object), arg2, method.Arguments[3]));

        Console.WriteLine(paramListExpr);

        var argValues = paramListExpr.Compile().Invoke();

        Console.WriteLine(argValues.Length);

        Console.WriteLine(Convert.ToInt64(argValues[0]));

        Console.WriteLine(argValues[1]);

    }

}