private void OPDPatientToolStripMenuItem_Click(object sender, EventArgs e)
        {
            this.Hide();
            OPDPatient opd = new OPDPatient();

            opd.Show();
        }
 private void MetroButtonBack_Click(object sender, EventArgs e)
 {
     if (this.IsUpdate)
     {
         this.Hide();
         OPDPatient l = new OPDPatient();
         l.Show();
     }
     else
     {
         this.Hide();
         PatientList l = new PatientList();
         l.Show();
     }
 }