Question

I am trying to close my c# console application (running without debugging) and nothing is working… i have tried all the usual suspects with different exit codes but nothing is terminating it =/ is it because the option is in a bunch of nested if statements? Its probably something really simple i’m missing but its hurting my brain now someone help please! I’ve tried :

System.Environment.Exit(0);
System.Environment.Exit(1);
System.Environment.Exit(-1);
return;
Application.Exit(); //(wont even except it)

if context helps i have used nested if statements to check if the user has inputted a number or the letter ‘q’ if they have inputted a number a calculation is carried out, if the have entered the letter q then the program is to exit and for anything else error statements are outputted.

string userInput;
int userInputDigit = 0;
double userCost = 0;
char userInputChar;

userInput = Convert.ToString(Console.ReadLine());

if (int.TryParse(userInput, out userInputDigit))
{
    if (userInputDigit <= 50)
    {
        userCost = (price * userInputDigit);
        Console.WriteLine("You have purchased {0} Widgets at a cost of {1:c0}", userInputDigit, userCost);
    }
    else if ((userInputDigit > 50) && (userInputDigit <= 80))
    {
        userCost = (price * 50) + ((userInputDigit - 50) * (price - 1));
        Console.WriteLine("You have purchased {0} Widgets at a cost of {1:c0}", userInputDigit, userCost);
    }
    else if ((userInputDigit > 80) && (userInputDigit <= 100))
    {
        userCost = (price * 50) + (30 * (price - 1)) + ((userInputDigit - 80) * (price - 2.50));
        Console.WriteLine("You have purchased {0} Widgets at a cost of {1:c0}", userInputDigit, userCost);
    }
    else
    {
        Console.WriteLine("Error! Please input a number between 0 and 100");
    }

}
else if (char.TryParse(userInput, out userInputChar))
{
    if ((userInput == "q") || (userInput == "Q"))
    {
        System.Environment.Exit(0);
    }
    else
    {
        Console.WriteLine("Incorrect Letter Inputted");
    }
}
else
{
    Console.WriteLine("Error! Please input a number or 'q' to quit");
}

Answer 1

Use a loop and just let Main return normally. Furthermore, I also tried to simplify the condition checking a bit along with the string comparison and parsing. Your error message suggests a validation range (“between” 0 and 100) that is not actually enforced by the preceding if/else if logic. For instance your first case (… <= 50) would be true if user enters a negative value. Also, I did not see where price was ever declared so I made up a constant in my example.

static bool ExitRequired(string line)
{
    return string.Equals(line, "q", StringComparison.OrdinalIgnoreCase);
}

static void Main(string[] args)
{
    const double price = 10;
    int userInputDigit;
    double userCost;
    string line = null;

    while (!ExitRequired(line))
    {
        Console.WriteLine("Enter a number or press 'q' to exit...");
        line = Console.ReadLine();

        if (ExitRequired(line))
            break;

        if (int.TryParse(line, out userInputDigit) 
            && userInputDigit > 0 
            && userInputDigit < 100)
        {
            if (userInputDigit <= 50)
            {
                userCost = (price * userInputDigit);
                Console.WriteLine("You have purchased {0} Widgets at a cost of {1:c0}", userInputDigit, userCost);
            }
            else if ((userInputDigit > 50) && (userInputDigit <= 80))
            {
                userCost = (price * 50) + ((userInputDigit - 50) * (price - 1));
                Console.WriteLine("You have purchased {0} Widgets at a cost of {1:c0}", userInputDigit, userCost);
            }
            else if ((userInputDigit > 80) && (userInputDigit <= 100))
            {
                userCost = (price * 50) + (30 * (price - 1)) + ((userInputDigit - 80) * (price - 2.50));
                Console.WriteLine("You have purchased {0} Widgets at a cost of {1:c0}", userInputDigit, userCost);
            }
        }
        else
        {
            Console.WriteLine("Error! Please input a number between 0 and 100");
        }
    }
}