This is my code for an ATM, but somehow when I press the number 2 on the numpad I get my else
statement that there was no choice for this number.
Console.WriteLine("What is your name? ");
string userName = Console.ReadLine();
Console.WriteLine("You are: " + userName);
Console.WriteLine("How much money do you have? ");
string Balance = Console.ReadLine();
float startBalance = float.Parse(Balance);
Console.WriteLine(userName + ", your balance is " + startBalance + " EUR");
Console.WriteLine("Press 1 for WITHDRAWAL");
Console.WriteLine("Press 2 for DEPOSIT");
if (Console.ReadKey().Key == ConsoleKey.NumPad1)
{
Console.ReadLine();
Console.WriteLine("How much money do you wish to withdraw? ");
string Withdrawal = Console.ReadLine();
float wBalance = float.Parse(Withdrawal);
Console.WriteLine("Your new balance is " + (startBalance - wBalance) + " EUR");
Console.ReadLine();
Environment.Exit(0);
}
if (Console.ReadKey().Key == ConsoleKey.NumPad2)
{
Console.ReadLine();
Console.WriteLine("How much money do you wish to deposit? ");
string Deposit = Console.ReadLine();
float dBalance = float.Parse(Deposit);
Console.WriteLine("Your new balance is " + (startBalance - dBalance) + " EUR");
Console.ReadLine();
Environment.Exit(0);
}
else Console.WriteLine("There was no choice for this number");
Copy + Paste is evil: please, note that subtracting (adding expected) deposit
"Your new balance is " + (startBalance - dBalance) + " EUR"
is a typical copy + paste error.
Instead of copying yourself, let's extract a method:
private static float ReadFloat(string title) {
// keep asking user...
while (true) {
if (!string.IsNullOrWhiteSpace(title))
Console.WriteLine(title);
if (!float.TryParse(Console.ReadLine(), out float result))
Console.WriteLine("Syntax error. Please, try again.");
else if (result < 0)
Console.WriteLine("Negative sum is not allowed. Please, try again.");
else
return result; // ... until valid value is provided
}
}
Then use it
...
Console.WriteLine("Press 1 for WITHDRAWAL");
Console.WriteLine("Press 2 for DEPOSIT");
// Ask user once - Console.ReadKey().Key - then operate with his/her choice
var choice = Console.ReadKey().Key;
// balance change (either negative - withdraw or positive - deposit)
float delta =
choice == ConsoleKey.NumPad1 ? -ReadFloat("How much money do you wish to withdraw?")
: choice == ConsoleKey.NumPad2 ? ReadFloat("How much money do you wish to deposit?")
: 0f;
if (delta != 0) {
Console.WriteLine($"Your new balance is {startBalance + delta} EUR");
Console.ReadLine();
Environment.Exit(0);
}
else
Console.WriteLine("There was no choice for this number");