CS5001 error C#

1

Doing the exercise for The Ultimate C# Series: Part 1 section Working With Text. The solution is as follows, but typing exactly as the solution yields the error code: CS5001: Program does not contain a static ‘Main’ method suitable for an entry point. Can someone suggest a solution? Thank you.

using System;
using System.Collections.Generic;

namespace CSharp1Exercises
{
public class Strings
{
///


/// Write a program and ask the user to enter a few numbers separated by a hyphen. Work out
/// if the numbers are consecutive. For example, if the input is “5-6-7-8-9” or “20-19-18-17-16”,
/// display a message: “Consecutive”; otherwise, display “Not Consecutive”.
///
public void Exercise1()
{
Console.Write("Enter a few numbers (eg 1-2-3-4): ");
var input = Console.ReadLine();

        var numbers = new List<int>();
        foreach (var number in input.Split('-'))
            numbers.Add(Convert.ToInt32(number));                

        numbers.Sort();

        var isConsecutive = true;
        for (var i = 1; i < numbers.Count; i++)
        {
            if (numbers[i] != numbers[i - 1] + 1)
            {
                isConsecutive = false;
                break;
            }
        }

        var message = isConsecutive ? "Consecutive" : "Not Consecutive";
        Console.WriteLine(message);
    }
2

Add the following Main function in class Strings
public static void Main(){
Exercise1();
}

Then, double click Properties in Solution Explorer, and set the Strings class as Statup project.

3

Thank you for your response.
I don’t quite follow your suggestion. Can you please copy and paste the entire text with your changes so that I can see exactly where the changes need to go?
Also I clicked on the name of the program in Solution Explorer (can’t double click just single click) but I don’t see anything called Startup project. Is there another place where this setting the String class as Startup project be done.

4

C#/.NET programs always need a Main() method, which is the method that is called to start your program. So without a Main() method, your program doesn’t start!

Try this:

using System;
using System.Collections.Generic;

namespace CSharp1Exercises
{
    public class Program
    {
        static void Main(string[] args)
        {
            Strings.Exercise1();
        }
    }

    public class Strings
    {
        ///
        /// Write a program and ask the user to enter a few numbers separated by a hyphen. Work out
        /// if the numbers are consecutive. For example, if the input is “5-6-7-8-9” or “20-19-18-17-16”,
        /// display a message: “Consecutive”; otherwise, display “Not Consecutive”.
        ///
        
        public static void Exercise1()
        {
            Console.Write("Enter a few numbers (eg 1-2-3-4): ");
            var input = Console.ReadLine();
            var numbers = new List<int>();
            foreach (var number in input.Split('-'))
                numbers.Add(Convert.ToInt32(number));

            numbers.Sort();

            var isConsecutive = true;
            for (var i = 1; i < numbers.Count; i++)
            {
                if (numbers[i] != numbers[i - 1] + 1)
                {
                    isConsecutive = false;
                    break;
                }
            }

            var message = isConsecutive ? "Consecutive" : "Not Consecutive";
            Console.WriteLine(message);
        }
    }
}