title: C# Program Validation
body: <p>I need some help making sure that when the user enters nothing, or not a number, it doesn't crash. I have it down so that it will tell them to enter a number if they don't, but I don't know how to make it go back to the original question and give them a chance to input correctly. Thanks for the help.</p>
  
  <pre><code>        Console.WriteLine("How much is rent: ");
          string  strRent = Console.ReadLine();
          double dblRent = 0.0;
          if (double.TryParse(strRent, out dblRent))
          {
              Console.WriteLine("How much is the car payment: ");
              string strCarPayment = Console.ReadLine();
              double dblCarPayment = Convert.ToDouble(strCarPayment);
          }
          else
          {
              Console.WriteLine("Enter a number");
          }
  
          Console.WriteLine("How much is student loan payment: ");
          string strStudentLoan = Console.ReadLine();
  
          Console.WriteLine("How much is phone bill: ");
          string strPhoneBill = Console.ReadLine();
  
          Console.WriteLine("How much is electric bill: ");
          string strElectricBill = Console.ReadLine();
  
          Console.WriteLine("Fraction deposited: ");
          string strFractionDeposited = Console.ReadLine();
  
          Console.WriteLine("Amount leftover: ");
          string strAmountLeft = Console.ReadLine();
  
  
  
          double dblStudentLoan = Convert.ToDouble(strStudentLoan);
          double dblPhoneBill = Convert.ToDouble(strPhoneBill);
          double dblElectricBill = Convert.ToDouble(strElectricBill);
          double dblFractionDeposited = Convert.ToDouble(strFractionDeposited);
          double dblAmountLeft = Convert.ToDouble(strAmountLeft);
  
          double dblBillSum = dblRent + dblCarPayment + dblStudentLoan + dblPhoneBill + dblElectricBill;
          double afterBills = dblAmountLeft / (1 - dblFractionDeposited);
          double totalPaycheck = afterBills + dblBillSum;
          Console.WriteLine("Total Paycheck: " + totalPaycheck.ToString("C"));
  
          Console.WriteLine("Enter wage $/hr: ");
          string strWage = Console.ReadLine();
  
          Console.WriteLine("Enter hours worked overtime: ");
          string strHoursOT = Console.ReadLine();
  
          Console.WriteLine("Enter overtime multiplier: ");
          string strOTWage = Console.ReadLine();
  
          double dblWage = Convert.ToDouble(strWage);
          double dblHoursOT = Convert.ToDouble(strHoursOT);
          double dblOTWage = Convert.ToDouble(strOTWage);
  
          double OTPay = (dblWage * dblOTWage) * dblHoursOT;
          Console.WriteLine("Overtime Pay: " + OTPay.ToString("C"));
          Console.ReadLine();
  
      }
  }
  </code></pre>
  
  <p>}</p>