#### Writing the code

We have to write the event ConvertCurrency() to convert the amount of levs in the selected currency:

private void ConvertCurrency()
{
var originalAmount = this.numericUpDownAmount.Value;
var convertedAmount = originalAmount;
if (this.comboBoxCurrency.SelectedItem.ToString() == "EUR")
{
convertedAmount = originalAmount / 1.95583m;
}
else if (this.comboBoxCurrency.SelectedItem.ToString() == "USD")
{
convertedAmount = originalAmount / 1.80810m;
}
else if (this.comboBoxCurrency.SelectedItem.ToString() == "GBP")
{
convertedAmount = originalAmount / 2.54990m;
}
this.labelResult.Text = originalAmount + " лв. = " +
Math.Round(convertedAmount, 2) + " " + this.comboBoxCurrency.SelectedItem;
}


The above code takes the amount for convert from the field numericUpDownAmount and the selected currency for the result from the field comboBoxCurrency. Then with a conditional statement, according to the selected currency, the amount is divided by the exchange rate (which is fixed in the source code). Finally, a text message with the result (rounded to second digit after the decimal point) is generated and recorded in the green box labelResult. Try it!

If you have problems with the example above, watch the video at the beginning of this chapter or ask in the forum of SoftUni: https://softuni.bg/forum.