Databinding problem in dropdownlist box by generics in C#

Question

I want to implement stack in my program by Genericx. I have a textbox and button to add elements in stack, a dropdownlist box and a button to bind total stack in dropdownlist box.

I have generic class and the code is below:

[Serializable]
public class myGenClass<T>
{
    private T[] _elements;
    private int _pointer;

    public myGenClass(int size)
    {
         _elements = new T[size];
        _pointer = 0;


    }

    public void Push(T item)
    {
        if (_pointer > _elements.Length - 1)
        {
            throw new Exception("Stack is full");

        }
        _elements[_pointer] = item;
        _pointer++;
    }

    public T Pop()
    {
        _pointer--;
        if (_pointer < 0)
        {

            throw new Exception("Stack is empty");
        }

        return _elements[_pointer];
    }

    public T[] myBind()
    {


        T[] showall = new T[_pointer];
        Array.Copy(_elements,showall, _pointer);
        T[] newarray = showall;
        Array.Reverse(showall);

        return showall;


    }

}

and my .cs page is below:

public partial class _Default : System.Web.UI.Page
{
    myGenClass<int> mystack = new myGenClass<int>(25);


         protected void Button1_Click(object sender, EventArgs e)
    {
        mystack.Push(Int32.Parse(TextBox1.Text));
        //DropDownList1.Items.Add(mystack.Pop().ToString());
        TextBox1.Text = string.Empty;
        TextBox1.Focus();
    }

    protected void Button2_Click(object sender, EventArgs e)
    {
        //string[] db;
        //db = Array.ConvertAll<int, string>(mystack.myBind(), Convert.ToString);
        DropDownList1.DataSource = mystack.myBind();
        DropDownList1.DataBind();
    }


}

but when I bind the datasource property of dropdownlist box to generic type return array (ie myBind()), it shows empty... Please help..

Answer 1

I haven't looked at the myGenClass type, but are you persisting the instance of myGenClass between requests? Each button click would post to a new instance of the _default class which initializes with an empty stack. If the stack isn't persisted between requests, it will contain its default values.