Enabling Linkbutton in GridView

DataTable dt = new DataTable(); 
dt.Load(reader);//reader is the sql data reader having db values
grdHold.DataSource = dt; grdHold.DataBind();
if (grdHold.Rows.Count >= 1)
{
  if (gvr.Cells[6].Text = "")
  {
        ((LinkButton)gvr.Cells[4].FindControl("lblHold")).Enabled=False;                   
  }

}