Is there a good way to use Console.ReadKey for choosing between values without doing alot of conversion between types?

Question

Im using Console.ReadKey() to choose from a number of options that varies from time to time. Before this initial code snippet there is a for loop that counts occurances into counter variable of type int.

The point is to use Console.ReadKey() to get an int.

int choice = ReadKey();
Console.WriteLine("");

if (choice < counter)
{
    mail.to = result[counter-1].email;
}

By using the following methods

static int ReadKey()
{
    ConsoleKeyInfo choice = Console.ReadKey();
    char convertedchoice = choice.KeyChar;
    string convertedchoice2 = convertedchoice.ToString();
    int result = TryInt(convertedchoice2);
    return result;
}

static int TryInt(string totry)
{
    while (true)
    {
        int result;
        if (int.TryParse(totry, out result))
        {
            return result;
        }
        Console.WriteLine("Sorry, you need to enter a number. Try again.");
    }
}

I tried using ToString() but this was the way that it would let me do it in the end. So this looks kind of inneffective to me and hence I would really appreciate some guidance as what to do differently?

Edit:

I ended up with a combination of all the good answers below. Thanks alot guys.

static int ReadKey()
{
    while (true)
    {
        ConsoleKeyInfo choice = Console.ReadKey();
        if (char.IsDigit(choice.KeyChar))
        {
            int answer = Convert.ToInt32(choice.KeyChar);
            return answer - 48; //-48 because 0 is represented in unicode by 48 and 1 by 49 etc etc
        }
        Console.WriteLine("\nSorry, you need to input a number");
    }
}

Answer 1

You can just call Convert.ToInt32(choice.KeyChar); directly.

That would simplify it a bit.

Answer 2

For a menu system with coiches 0..9 this is reasonably OK. Not for reading larger numbers though.

Your whole checking logic can be made a lot easier with char.IsDigit() :

if char.IsDigit(convertedchoice)
{
  int result = convertedchoice - '0';
  return result;
}
else ...

Answer 3

There are lots of ways to simplify your code, but for a start try to avoid putting everything into a variable. In general, things like:

(a + b + c) / 2

are much easier to read than things like:

int A_plus_B = a + b
int A_plus_B_plus_C = A_plus_B + c
int answer = A_plus_B_plus_C / 2

With this in mind, you could write:

static int ReadKey()
{
    while (true)
    {
        char ch = Console.ReadKey().KeyChar;
        int result;
        if (int.TryParse(ch.toString(), out result))
        {
            return result;
        }
    }
}