using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Threading.Tasks;

namespace ConfigurationFileParser
{

    /// <summary>
    /// Base class describing rules of the specified type of element.
    /// </summary>
    public abstract class AbstractElement<T> where T : AbstractElement<T>, new()
    {
        /// Type of the element on which the element is applied.
        /// </summary>
        protected ElementType ElementTypeValue;
        /// <summary>
        /// Element comment.
        /// </summary>
        protected string comment;
        /// <summary>
        /// Definition whether the element is array.
        /// </summary>
        private bool isArrayValue;
        /// <summary>
        /// Current content of line.
        /// </summary>
        private Line content;

        /// <summary>
        /// Desfault constructor of the AbstractElementRule class.
        /// </summary>
        protected AbstractElement()
        {
        }

        /// <summary>
        /// Gets the type of the element on which the rule is applied.
        /// </summary>
        public ElementType ElementType
        {
            get
            {
                return ElementTypeValue;
            }
        }

        /// <summary>
        /// Gets the definition whether the element is array.
        /// </summary>
        public bool IsArray()
        {
            return isArrayValue;
        }

        /// <summary>
        /// Sets the comment related to this line.
        /// </summary>
        public bool SetComment(string tmp)
        {
            comment = tmp;
            return true;
        }

        /// <summary>
        /// Parses Element from the lines of the rule description.
        /// </summary>
        /// <returns>The Element description object for the specified type if description is valid otherwise null.</returns>
        /// <param name="logFile">log file where error messages are printed</param>
        /// <param name="element">Line of the Element description</param>
        /// <exception cref="NotImpelementedException">Method in base class is not implemented.</exception>
        public static T ParseElement(StreamWriter logFile, Line element)
        {
            throw new NotImplementedException("Method not implemented please use the overriden method of the descendants.");
        }
    }
}

namespace ConfigurationFileParser
{
    public class ArrayOfElements : AbstractElement<ArrayOfElements>
    {
        /// <summary>
        /// Type of the array.
        /// </summary>
        protected ElementType ElementTypeValue;

        /// <summary>
        /// Contains array of Elements.
        /// </summary>
        protected AbstractElement[] elements;


    }
}

// Создаю массив наследников.
        var arr = new AbstactElement<object>[5];
        arr[0] = new A2<object>();
        arr[1] = new A3<object>();
        arr[2] = new A2<object>();
        arr[0].data = '5';
        arr[1].data = "dummystring";
        arr[2].data = new List<int>();
        var a = (List<int>)arr[2].data;
        a.Add(2341);
        Console.WriteLine((arr[2].data as List<int>)[0]);

public abstract class AbstactElement<T>
{
    public object data;
}

public class A2<T> : AbstactElement<T>
{

}

public class A3<T> : AbstactElement<T>
{

}