如何使用 C# 创建 Web 应用程序，使用 macOS X 创建 ASP.NET 核心

Question

I'm the beginner in C# and in ASP.NET Core and I have a task to create Web Application. The main task of this app is basic: I need to create a form(line where user can write something) and display written content. Also it mush handle exceptions(FormatException) when user doesn't input a number

Code snippet for Console Application I have developed and now I need to transform it into Web Application with the help of C# and ASP.NET Core framework.

Here the code template of C# Console Application:

using System;
namespace Input_Output
{
   class MainClass
   {
     public static void Main(string[] args)
     {
        int number;
        try 
        {
           Console.WriteLine("Enter a number: ");
           number = Convert.ToInt32(Console.ReadLine());
           Console.WriteLine($"You've entered {number}");
        }
        catch(FormatException)
        {
          Console.WriteLine("It is not a number!!!");
        }
        Console.ReadKey(true);
     }
   }
}

And now I need to transform it into the Web Application with the line for input and if it is not a numeric value like 10, 49, etc than display exception in the special window. I am writing this on macOS X, so don't give pieces of advice for Windows:)

Hope someone could help me with this task. Thank you:):):)

Answer 1

    int number;
    try 
    {
       Console.WriteLine("Enter a number: ");
       var enteredNumber = Console.ReadLine();
       var isNumeric = int.TryParse(enteredNumber, out int n);
       if(isNumeric)
       {
         number = Convert.ToInt32(enteredNumber);
         Console.WriteLine($"You've entered {number} succesfully");
       }
       else
       {
         Console.WriteLine("It is not a number!!!");
       }
    }
    catch(Exception ex)
    {
      Console.WriteLine("An issue occured with your number entry: " + ex.message);
    }
    Console.ReadKey(true);