private void btnAdd_reg_Click(object sender, EventArgs e)
{
this.Close();
OPD_Registration opdreg = new OPD_Registration();
opdreg.Show();
}
private void OPDbill_Load(object sender, EventArgs e)
{
txtBill_Date.Text = DateTime.Now.ToLongDateString();
var OPID = new OPD_Registration();
OPID.Show(this);
txtPatient.Text = OPID.PIDvalue;
OPID.Dispose();
Token();
AutoGenerateBID();
}