private void withdrawButton_Click(object sender, EventArgs e) { if (string.IsNullOrEmpty(withdrawFromAddress.Text)) { MessageBox.Show("Please insert source address"); return; } var symbol = withdrawAssetComboBox.SelectedItem.ToString(); int amount = int.Parse(withdrawAmount.Text); if (amount <= 0) { MessageBox.Show("Please insert a valid amount of " + symbol); return; } api.WithdrawAsset(keyPair, withdrawFromAddress.Text, symbol, amount); }