how to pass arraylist to switch statement

i want to pass arraylist to switch statement , below is the code:

 protected void CheckBoxList1_SelectedIndexChanged(object sender, EventArgs e)
{

     ArrayList myList = new ArrayList();
    foreach (ListItem listitem in CheckBoxList1.Items)
    {
        if (listitem.Selected)
            myList.Add(listitem.Value);

    }

    ViewState["myList"] = myList;

    CurrentPage = 0;
    BindGrid();


}
 private void BindGrid()
{

    DataTable dt = null;

    switch (ViewState["myList"]) //gives an error
    { case myList[1]:  dt = caravans.GetSelectedFilter(myList); break;
    default:  dt = caravans.GetAllCaravans(); break;

    pds.DataSource = dt.DefaultView;
    pds.AllowPaging = true;
    pds.PageSize = 12;//add the page index when item exceeds 12     //Convert.ToInt16(ddlPageSize.SelectedValue);
    pds.CurrentPageIndex = CurrentPage;
    DataList1.RepeatC开发者_StackOverflow中文版olumns = 4; // 4 items per line
    DataList1.RepeatDirection = RepeatDirection.Horizontal;

    DataList1.DataSource = pds;
    DataList1.DataBind();

 //   lnkbtnNext.Enabled = !pds.IsLastPage;
    ImageButton2.Enabled = !pds.IsLastPage;
   // lnkbtnPrevious.Enabled = !pds.IsFirstPage;

    doPaging();

}

From MSDN:

The governing type of a switch statement is established by the switch expression. If the type of the switch expression is sbyte, byte, short, ushort, int, uint, long, ulong, char, string, or an enum-type, then that is the governing type of the switch statement. Otherwise, exactly one user-defined implicit conversion (Section 6.4) must exist from the type of the switch expression to one of the following possible governing types: sbyte, byte, short, ushort, int, uint, long, ulong, char, string. If no such implicit conversion exists, or if more than one such implicit conversion exists, a compile-time error occurs.

The Switch Statement