private void CRReceiptButton_Click(object sender, EventArgs e)
{
if (receipt == null)
{
receipt = new ReceiptForm();
receipt.MdiParent = this;
receipt.Dock = DockStyle.Fill;
receipt.Show();
receipt.FormClosed += Receipt_FormClosed;
}
else
{
receipt.Activate();
}
}
private void Receipt_FormClosed(object sender, FormClosedEventArgs e)
{
receipt = null;
}