I found the solution as follows:
private void gridView1_RowCellClick(object sender, DevExpress.XtraGrid.Views.Grid.RowCellClickEventArgs e)
{
TBGRNo.Text = gridView1.GetRowCellValue(gridView1.FocusedRowHandle, "GRNo").ToString();
TBSName.Text = gridView1.GetRowCellValue(gridView1.FocusedRowHandle, "SName").ToString();
TBFName.Text = gridView1.GetRowCellValue(gridView1.FocusedRowHandle, "FName").ToString();
}