Adding a Form to an existing console application?

I need to add a form to my existing application i have it all laid out but how do I get it to use the code from the form as to make it seamless. Any thoughts? and sorry for the wall of code just thought it might help.

The Validate button should get its info from the console like below

The Generate action should append the check digit like in this example

   public static void Main(string[] args)
    {
        Console.Write("Enter a valid 10 digit ISBN Number ");
        string isbn = isb开发者_如何学JAVAnChecker.DestabilizeIsbn(Console.ReadLine()); // Normalizes the input and puts it on string "str"
        if (isbn.Length > 10 || isbn.Length < 9) // If the string length is greather than 10, or smaller than 9
        {
            Console.WriteLine("The number you have entered is not a valid ISBN try again."); // Print invalid number
            Console.ReadLine();
        }
        else if (isbn.Length == 10) // If the length is 10
        {
            if (isbnChecker.CheckNumber(isbn)) // If function CheckNum return "true"...
                Console.WriteLine("The number you have entered is a valid ISBN");

            else // If it returns "false"...
                Console.WriteLine("The number you have entered is not a valid ISBN try again.");
                Console.ReadLine();
        }
        else // Else (If the number is NOT greater than 10 or smaller than 9, NOR is it 10 -> If the number is 9)
        {
            Console.WriteLine("The Check digit that corresponds to this ISBN number is " + checkIsbnClass.CheckIsbn(isbn) + "."); // Print the checksum digit
            Console.ReadLine();
        }



    }



 public static class isbnChecker
    {
        public static bool CheckNumber(string isbn) // Checks if the checksum digit is correct
        {
            if (isbn[9].ToString() == checkIsbnClass.CheckIsbn(isbn)) // If the 10th digit of the number is the same as the calculated digit...
                return true;
            else // If they're not the same...
                return false;
        }
        public static string DestabilizeIsbn(string isbn) // replace the string
        {
            return isbn.Replace("-", "").Replace(" ", "");
        }
    }

  public static string CheckIsbn(string isbn) // Calculates the 10th digit of a 9-digits partial ISBN number
        {
            int sum = 0;
            for (int i = 0; i < 9; i++) // For each number...
            {
                sum += int.Parse(isbn[i].ToString()) * (i + 1); // ...Multiply the number by it's location in the string
            }
            if ((sum % 11) == 10) // If the remainder equals to 10...
            {
                return "x"; // Output X
            }
            else // If it does not equal to 10...
            {
                return (sum % 11).ToString(); // Output the number
            }
        }
      public static bool CheckNumber(string isbn) // Checks if the checksum digit is correct
        {
            if (isbn[9].ToString() == CheckIsbn(isbn)) // If the 10th digit of the number is the same as the calculated digit...
                return true;
            else // If they're not the same...
                return false;
        }
      public static string DestabilizeIsbn(string isbn) // replace the string
      {
          return isbn.Replace("-", "").Replace(" ", "");
      }

    }


public partial class IsbnForm : Form
{
    public IsbnForm()
    {
        InitializeComponent();
    }

    private void textBox1_TextChanged(object sender, EventArgs e)
    {
        this.xInputTextBox.Text = "Enter a Valid ISBN";
    }
}

}

I'm not sure what you're asking here. If you want the user to enter the ISBN in the form, then you'd do this:

using (var frm = new IsbnForm())
{
    var rslt = frm.ShowDialog();
    if (rslt == DialogResult.OK)
    {
        // Access property that gets the value the user entered.
    }
    else
    {
        // User canceled the form somehow, so show an error.
    }
}

If you want to display the form and have the entry field displaying the ISBN that the user entered on the command line, then you'll need to add a property or method to the IsbnForm class so that you can set the value before displaying the form. That is, inside IsbnForm, add this property:

public string Isbn
{
    get { return xInputTextBox.Text; }
    set { xInputTextBox.Text = value; }
}

And then, to populate it:

Console.Write("Enter an ISBN: ");
var isbn = Console.ReadLine();
using (var frm = new IsbnForm())
{
    frm.Isbn = isbn;  // populates the field in the form.
    var rslt = frm.ShowDialog();
    // etc, etc.
}