GridView - Confirm MessageBox before Deleting

    public static void AddConfirmDelete(GridView gv, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            foreach (DataControlField dcf in gv.Columns)
            {
                CommandField cf = dcf as CommandField;
                if (cf != null)
                {
                    TableCell cell = e.Row.Cells[gv.Columns.IndexOf(dcf)];
                    foreach (Control ctl in cell.Controls)
                    {
                        switch (cf.ButtonType)
                        {
                            case ButtonType.Button:
                                if (ctl is Button && ((Button)ctl).Text == cf.DeleteText)
                                {
                                    Button btn = (Button)ctl;
                                    //btn.OnClientClick = "return confirm(\"Are you sure?\")";
                                    btn.Attributes.Add("onclick", "return confirm(\"Are you sure Button?\")");
                                }


                                if (ctl is Button && ((Button)ctl).Text == cf.EditText)
                                {
                                    Button btn = (Button)ctl;
                                    //btn.OnClientClick = "return confirm(\"Are you sure?\")";
                                    btn.Attributes.Add("onclick", "return confirm(\"Are you sure EditText?\")");
                                }
                                break;
                            case ButtonType.Image:
                                if (ctl is ImageButton && ((ImageButton)ctl).ImageUrl == cf.DeleteImageUrl)
                                {
                                    ImageButton ib = (ImageButton)ctl;
                                    //ib.OnClientClick = "return confirm(\"Are you sure?\")";
                                    ib.Attributes.Add("onclick", "return confirm(\"Are you sure Image?\")");
                                }

                                if (ctl is Button && ((Button)ctl).Text == cf.EditText)
                                {
                                    Button btn = (Button)ctl;
                                    //btn.OnClientClick = "return confirm(\"Are you sure?\")";
                                    btn.Attributes.Add("onclick", "return confirm(\"Are you sure EditImage?\")");
                                }
                                break;
                            case ButtonType.Link:
                                if (ctl is LinkButton && ((LinkButton)ctl).Text == cf.DeleteText)
                                {
                                    LinkButton lb = (LinkButton)ctl;
                                    lb.Attributes.Add("onclick", "return confirm(\"Are you sure Link?\")");
                                }

                                if (ctl is LinkButton && ((LinkButton)ctl).Text == cf.EditText)
                                {
                                    LinkButton lb = (LinkButton)ctl;
                                    lb.Attributes.Add("onclick", "return confirm(\"Are you sure EditLink?\")");
                                }
                                break;
                        }

                    }
                }
            }
        }
    }