Currency convertor

iJunior_C#_Lesson_26

using System.Diagnostics;

namespace iJuniorPractice;

class Program
{
    static void Main(string[] args)
    {
        const int CommandexchangeRateRubToUsd = 1;
        const int CommandexchangeRateRubToEuro = 2;
        const int CommandexchangeRateUsdToRub = 3;
        const int CommandexchangeRateEuroToRub = 4;
        const int CommandexchangeRateEuroToUsd = 5;
        const int CommandexchangeRateUsdToEuro = 6;
        const int CommandExit = 7;

        string[] menuTextArray = 
        {
            "Main Menu:",
            $"{CommandexchangeRateRubToUsd} - Convert Rub to Usd.",
            $"{CommandexchangeRateRubToEuro} - Convert Rub to Euro.",
            $"{CommandexchangeRateUsdToRub} - Convert Usd to Rub.",
            $"{CommandexchangeRateEuroToRub} - Convert Euro to Rub.",
            $"{CommandexchangeRateEuroToUsd} - Convert Euro to Usd.",
            $"{CommandexchangeRateUsdToEuro} - Convert Usd to Euro.",
            $"{CommandExit} - Exit."
        };
        string enterCommandRequestText = "Enter your command: ";
        string enterValueRequstText = "Enter value to convert (use \",\" to enter non-integral): ";
        string errorCommandText = "Error, incorrect command";
        string errorValueEntered = "Error, enter digit.";
        string errorMaxValue = "Error, entered value is too big, try again...";
        string continueMessage = "Press any key to continue...";
        string exitMessage = "Goodbye...";
        float balanceRub = 100;
        float balanceEuro = 100;
        float balanceUsd = 100;
        float exchangeRateRubToUsd = 0.01219f;
        float exchangeRateUsdToRub = 82.03f;
        float exchangeRateRubToEuro = 0.01073f;
        float exchangeRateEuroToRub = 93.19f;
        float exchangeRateUsdToEuro = 0.88487f;
        float exchangeRateEuroToUsd = 1.1301f;
        bool isConvert = true;
        int enteredCommand;
        float enteredConvertValue;

        while (isConvert)
        {
            Console.Clear();
            
            for (int i = 0; i < menuTextArray.Length; i++)
            {
                Console.WriteLine(menuTextArray[i]);
            }
            
            Console.WriteLine($"balance: Usd - {balanceUsd}, Euro - {balanceEuro}, Rub - {balanceRub}");
            Console.WriteLine(enterCommandRequestText);

            while (int.TryParse(Console.ReadLine(), out enteredCommand) == false)
            {
                Console.WriteLine(errorValueEntered);
            }
            
            switch (enteredCommand)
            {
                case CommandexchangeRateRubToUsd:
                    Console.WriteLine(enterValueRequstText);

                    while (float.TryParse(Console.ReadLine(), out enteredConvertValue) == false)
                    {
                        Console.WriteLine(errorValueEntered);
                    }

                    if (balanceRub - enteredConvertValue >= 0)
                    {
                        balanceRub -= enteredConvertValue;
                        balanceUsd += enteredConvertValue * exchangeRateRubToUsd;
                    }
                    else
                    {
                        Console.WriteLine(errorMaxValue);
                    }
                    break;
                
                case CommandexchangeRateRubToEuro:
                    Console.WriteLine(enterValueRequstText);

                    while (float.TryParse(Console.ReadLine(), out enteredConvertValue) == false)
                    {
                        Console.WriteLine(errorValueEntered);
                    }

                    if (balanceRub >= enteredConvertValue)
                    {
                        balanceRub -= enteredConvertValue;
                        balanceEuro += enteredConvertValue * exchangeRateRubToEuro;
                    }
                    else
                    {
                        Console.WriteLine(errorMaxValue);
                    }
                    break;

                case CommandexchangeRateUsdToRub:
                    Console.WriteLine(enterValueRequstText);

                    while (float.TryParse(Console.ReadLine(), out enteredConvertValue) == false)
                    {
                        Console.WriteLine(errorValueEntered);
                    }

                    if (balanceUsd >= enteredConvertValue)
                    {
                        balanceUsd -= enteredConvertValue; 
                        balanceRub += enteredConvertValue * exchangeRateUsdToRub; 
                    }
                    else
                    {
                        Console.WriteLine(errorMaxValue);
                    }
                    break;
                
                case CommandexchangeRateEuroToRub:
                    Console.WriteLine(enterValueRequstText);

                    while (float.TryParse(Console.ReadLine(), out enteredConvertValue) == false)
                    {
                        Console.WriteLine(errorValueEntered);
                    }

                    if (balanceEuro >= enteredConvertValue)
                    {
                        balanceEuro -= enteredConvertValue;
                        balanceRub += enteredConvertValue * exchangeRateEuroToRub;
                    }
                    else
                    {
                        Console.WriteLine(errorMaxValue);
                    }
                    break;
                
                case CommandexchangeRateEuroToUsd:
                    Console.WriteLine(enterValueRequstText);

                    while (float.TryParse(Console.ReadLine(), out enteredConvertValue) == false)
                    {
                        Console.WriteLine(errorValueEntered);
                    }

                    if (balanceEuro >= enteredConvertValue)
                    {
                        balanceEuro -= enteredConvertValue;
                        balanceUsd += enteredConvertValue * exchangeRateEuroToUsd;
                    }
                    else
                    {
                        Console.WriteLine(errorMaxValue);
                    }
                    break;
                
                case CommandexchangeRateUsdToEuro:
                    Console.WriteLine(enterValueRequstText);

                    while (float.TryParse(Console.ReadLine(), out enteredConvertValue) == false)
                    {
                        Console.WriteLine(errorValueEntered);
                    }

                    if (balanceUsd >= enteredConvertValue)
                    {
                        balanceUsd -= enteredConvertValue;
                        balanceEuro += enteredConvertValue * exchangeRateUsdToEuro;
                    }
                    else
                    {
                        Console.WriteLine(errorMaxValue);
                    }
                    break;
                
                case CommandExit:
                    isConvert = false;
                    Console.WriteLine(exitMessage);
                    break;
                
                default:
                    Console.WriteLine(errorCommandText);
                    break;
            }

            Console.WriteLine(continueMessage);
            Console.ReadLine();
        }
    }
}