add a JS:confirm() to delete(include update) button

this.DataGrid1.ItemCommand += new System.Web.UI.WebControls.DataGridCommandEventHandler(this.DataGrid1_ItemCommand);
private void DataGrid1_ItemCreated(object sender, System.Web.UI.WebControls.DataGridItemEventArgs e)
{
ListItemType lit = e.Item.ItemType;
if (lit == ListItemType.Item || lit == ListItemType.AlternatingItem)
{
ModufyItem(e);
}
}
private void ModufyItem(DataGridItemEventArgs e)
{
WebControl wc;
int i = e.Item.Cells.Count -1;//here as the delete button is in the lastest cell
wc = ((WebControl) e.Item.Cells[i]);
wc.Height = 25; //set the button style
wc.Width = 50;
String javascript = "return confirm('Delete it??');"; //here is the js to be added
wc.Attributes.Add("onclick", javascript);
wc.ToolTip = e.Item.Cells[2].Text.Trim() + "...";
wc.ToolTip += "Delete this row";
}