C# – Problem in event generation of dynamically generated CheckBox

I have a datagrid with dynamically generated checkbox column..I am not able to
generate the checkedChanged event for the checkbox..

Here is my code:

public class ItemTemplate : ITemplate
{
    //Instantiates the checkbox
    void ITemplate.InstantiateIn(Control container)
    {
        CheckBox box = new CheckBox();            
        box.CheckedChanged += new EventHandler(this.OnCheckChanged);
        box.AutoPostBack = true;
        box.EnableViewState = true;
        box.Text = text;
        box.ID = id;
        container.Controls.Add(box);
    }

    public event EventHandler CheckedChanged;

    private void OnCheckChanged(object sender, EventArgs e)
    {
        if (CheckedChanged != null)
        {
            CheckedChanged(sender, e);
        }
    }
}

and Here is the event

private void OnCheckChanged(object sender, EventArgs e)
{

}

Thanks In advance