看了网上都说是在CellFormatting事件中设置，但是设置以后，发现刷新的很厉害，不知为何？求指教，我的代码：

            //if (e.RowIndex > -1)
            //{
            //    DataRowView drv = gridEmail.Rows[e.RowIndex].DataBoundItem as DataRowView;

            //    if (drv["T_Mail_ReadState"].ToString() == bool.TrueString) return;
            //    //如果未读设置字体加粗
            //    if (gridEmail.Columns[e.ColumnIndex].GetType() == typeof(DataGridViewTextBoxColumn))
            //    {
            //        gridEmail.Rows[e.RowIndex].DefaultCellStyle = ReadedMailRowStateCellStyle;
            //    }
            //}