private void msbTrans_FA_DLBankRecieptVoucher_Click(object sender, EventArgs e) { if (childBankRecieptVoucher == null || childBankRecieptVoucher.Text == "") { childBankRecieptVoucher = new BankRecieptVoucher(); childBankRecieptVoucher.MdiParent = this; childBankRecieptVoucher.Show(); } }