Question

I am struggling with this assignment. I can't get the program to run when I enter a number with the $ symbol followed by a number below 10. any help would be greatly appreciated.

Create a program named Auction that allows a user to enter an amount bid on an online auction item. Include three overloaded methods that accept an int, double, or string bid. Each method should display the bid and indicate whether it is over the minimum acceptable bid of $10. If the bid is a string, accept it only if one of the following is true: it is numeric and preceded with a dollar sign, or it is numeric and followed by the word dollars. Otherwise, display a message that indicates the format was incorrect.

class Auction
    {
        public static void Main(string[] args)
        {
            string bidamount;
            Console.Write("Enter bid: ");
            bidamount = Console.ReadLine();
            double num;
            int n;

            if (double.TryParse(bidamount, out num))
            {
                double bid = Convert.ToDouble(bidamount);

                if (valid(bid))
                {
                    Console.WriteLine("Bid is $" + bid + ".");
                    Console.WriteLine("Bid is at/over $10.");
                    Console.WriteLine("Bid accepted.");
                }
                else
                    Console.WriteLine("Invalid. Bid not acceptable.");
            }
            else if (int.TryParse(bidamount, out n))
            {
                int bid = Convert.ToInt32(bidamount);
                if (valid(bid))
                {
                    Console.WriteLine("Bid is $" + bid + ".");
                    Console.WriteLine("Bid is at/over $10.");
                    Console.WriteLine("Bid accepted.");
                }
                else
                    Console.WriteLine("Bid not acceptable.");
            }
            else
            {
                string bid = (bidamount);
                if (valid(bidamount))
                {
                    Console.WriteLine("Bid is $" + bid + ".");
                    Console.WriteLine("Bid is at/over $10.");
                    Console.WriteLine("Bid accepted.");
                }
                else
                    Console.WriteLine("Bid not acceptable.");
            }
            Console.ReadKey();
        }
        public static bool valid(int bid)
        {
            if (bid < 10)
                return false;
            else
                return true;
        }
        public static bool valid(double bid)
        {
            if (bid < 10)
                return false;
            else
                return true;
        }
        public static bool valid(string bid)
        {
            if (bid[0] == '$' && Convert.ToInt32(bid.Substring(1)) >= 10)
                return true;
            else if ((Convert.ToInt32(bid.Substring(0, 2)) >= 10) && (bid.Substring(2).Equals("dollars")))
            {
                return true;
            }
            else
                return false;
        }
    }

Answer 1

Here is the completed code for this problem. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks

using System;

class Auction {
    public static void Main(string[] args) {
        string bidamount;
        Console.Write("Enter bid: ");
        bidamount = Console.ReadLine();
        double num;
        int n;

        if (double.TryParse(bidamount, out num)) {
            double bid = Convert.ToDouble(bidamount);

            if (valid(bid)) {
                Console.WriteLine("Bid is $" + bid + ".");
                Console.WriteLine("Bid is at/over $10.");
                Console.WriteLine("Bid accepted.");
            }
            else Console.WriteLine("Invalid. Bid not acceptable.");
        }
        else if (int.TryParse(bidamount, out n)) {
            int bid = Convert.ToInt32(bidamount);
            if (valid(bid)) {
                Console.WriteLine("Bid is $" + bid + ".");
                Console.WriteLine("Bid is at/over $10.");
                Console.WriteLine("Bid accepted.");
            }
            else Console.WriteLine("Bid not acceptable.");
        }
        else {
            string bid = (bidamount);
            if (valid(bidamount)) {
                //bid is either in '$num' or 'num dollars' format, so we dont have
                //to prepend '$' symbol
                Console.WriteLine("Bid is " + bid + ".");
                Console.WriteLine("Bid is at/over $10.");
                Console.WriteLine("Bid accepted.");
            }
            else Console.WriteLine("Bid not acceptable.");
        }
        Console.ReadKey();
    }
    public static bool valid(int bid) {
        if (bid < 10) return false;
        else return true;
    }
    public static bool valid(double bid) {
        if (bid < 10) return false;
        else return true;
    }

    //updated this method
    public static bool valid(string bid) {

        double num;
        //trying first way of checking if the input is a dollar sign followed by a numeric
        //value
        if (bid.Length > 0 && bid[0] == '$' && double.TryParse(bid.Substring(1), out num)) {
            //yes, checking if the numeric value is greater than or equal to 10
            if (num >= 10) {
                //valid
                return true;
            } else {
                return false;
            }
        }
        num = 0;
        //trying second check to see if the input is a numeric value followed by the word
        //dollars.
        if (bid.Length > 0 && bid.Contains("dollars") && double.TryParse(bid.Substring(0, bid.IndexOf("dollars")), out num)) {
            //yes, checking if num>=10
            if (num >= 10) {
                //valid
                return true;
            } else {
                return false;
            }
        }
        //invalid format
        return false;

    }
}

/*OUTPUT (multiple runs)*/

Enter bid: $19

Bid is $19.

Bid is at/over $10.

Bid accepted.

Enter bid: 11 dollars

Bid is 11 dollars.

Bid is at/over $10.

Bid accepted.