.net GridView更改某一行的背景顏色

如果“是否有效”這一列的数据为无效的话，将这一行设置为灰色，效果如下
protected void gvCertificateCN_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
#region Check Box 全选

        DataSet dt = (DataSet)gvCertificateCN.DataSource;
        int tempStatus = 0;
        int.TryParse(dt.Tables[0].Rows[e.Row.RowIndex]["RecId"].ToString(), out tempStatus);

 //遍历所有行设置边框样式
        foreach (TableCell tc in e.Row.Cells)
        {
            if (dt.Tables[0].Rows[e.Row.RowIndex]["isValid"].ToString() == "無效")
            {
                tc.Attributes["style"] = "background-color:LightGray";
            }
        }

        ImageButton btnDelete = (ImageButton)e.Row.FindControl("btnDelete");
        CWebUtil.setImageButtonEnabled(btnDelete, true);
        btnDelete.Attributes.Add("onclick", "return confirm("你确定要删除此条记录吗？");");

        #endregion
    }
}