private void btnAddItem_Click(object sender, EventArgs e)
{
Forms.BillBody body = new BillBody(this.head);
body.MdiParent = this.MdiParent;
body.Show();
RefreshChildGrid();
}
private void btnSave_Click(object sender, EventArgs e)
{
head.Save(head);
Forms.BillBody body = new BillBody(head);
body.MdiParent = this.MdiParent;
this.Close();
body.Show();
}