private void button2_Click(object sender, EventArgs e)
 {
     ReceiptList receiptList = new ReceiptList();
     receiptList.Show();
     this.Hide();
 }
 private void cancel_ReceiptAdd(object sender, EventArgs e)
 {
     ReceiptList receiptList = new ReceiptList();
     receiptList.Show();
     this.Visible = false;
 }