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C#

Posted by Charlie Harcourt
Charlie Harcourt
8,045 Points

Calculator - bonus work

Comilation failed: 5 error(s), 0 warnings

Why is it not working?

URL to code: https://w.trhou.se/hh7wu1g8x4

3 Answers

Izabela Matos
Izabela Matos
6,302 Points
Izabela Matos
Izabela Matos
6,302 Points

1) You forgot to parse a few integers through your code

2) on line 16 you wrote

           if(num1.ToLower() == "quit")

but int variables don't accept .ToLower() methods. the same mistake was made on line 36

3) on line 22 you wrote

num1 = double.Parse(userAnswer)

but userAnswer doesn't seem to exist anywhere else on your code

4) in this part of your code, you should take out the "int" in front of your runningTotal variables, cause you have already declared it on the 1st line of the program

if (op == '+')
                {
                    int runningTotal = num1 + num2;

                }
                else if (op == "-")
                {
                    int runningTotal = num1 - num2;

                }
                else if (op == "/")
                {
                    int runningTotal = num1 / num2;

                }
                else if (op == "*")
                {
                    int runningTotal = num1 * num2;

these are the ones I was able to catch ^~^

Charlie Harcourt
Charlie Harcourt
8,045 Points

Yes helped thanks :D still getting plenty of errors though.. hmm D: http://w.trhou.se/sn871ual7g

Charlie Harcourt
Charlie Harcourt
8,045 Points
Charlie Harcourt
Charlie Harcourt
8,045 Points

Steven Parker woud you be able to add anything on? Please :)

Steven Parker
Steven Parker
221,322 Points
Steven Parker
Steven Parker
221,322 Points

:bell: Hi, I got alerted by your tag.

It looks like you might have prior experience with a language like JavaScript or Python. But in C#, variables have a specific type that cannot be changed. So you'll need to keep your strings/ints/doubles/etc. separate.

For example:

              string ans1 = Console.ReadLine();  // need a string here
              double num1;                       // reserve a double for later

              if (ans1 == "quit")                // compare the string
              {
                  break;
              }
              else 
              {
                  num1 = double.Parse(ans1);     // convert to a double
              }

You'll also need to do something similar for the second number.

Charlie Harcourt
Charlie Harcourt
8,045 Points

Ok, so when I run this I get far less mistakes, however i'm getting errors like "Operator == cannot be applied to operands of type method group and string" I don't quite understand what this means?

using System; namespace Calculator { class Arithmatic { static void Main() { var runningTotal = 0.0; while(true) {

           //Prompt User for a number
          Console.WriteLine("Please type a number");
          var ans1 = Console.ReadLine();
          double num1;

          if(ans1.ToLower == "quit")
            {
              break;
            }

            else 
            {
              num1 = double.Parse(num1);
            }

            //Prompt the User for an operation
            Console.WriteLine("Type in a operation + - / *");
            var ans2 = Console.ReadLine();

            if(ans2.ToLower == "quit")
            {
              break;
            }

            //Prompt the user for another number
            Console.WriteLine("Please type a number");
            var ans3 = Console.ReadLine();
            double num2;

            if(num2 == "quit")
            {
              break;
            }
            else
            {    
              num2 = double.Parse(num2);      
            }
            //Prefprm the operation
            if(ans2 == "+")
            {
               runningTotal = num1 + num2;

            }
            else if(ans2 == "-") 
            {
               runningTotal = num1 - num2;

            }
            else if(ans2 == "/") 
            {
              runningTotal = num1 / num2;

            }
            else if(ans2 == "*") 
            {
               runningTotal = num1 * num2;

            }        
            Console.WriteLine("Your number is " + runningTotal + ".");
          }
            Console.WriteLine("Bye");
    }
}

}

Steven Parker
Steven Parker
221,322 Points
Steven Parker
Steven Parker
221,322 Points

That's another case where different types are being compared. You're seeing "method group" as the type when you name the method (using no parentheses) instead of call it (using parentheses) like on line 18:

//          if (ans1.ToLower == "quit")    <-- name alone is a "method group"
            if (ans1.ToLower() == "quit")  //   parentheses after name CALL the method

And there are still several cases where you need to separate strings from doubles or ints, like on line 25:

//              num1 = double.Parse(num1);  <-- can't convert from a double (or itself)
                num1 = double.Parse(ans1);  //  but convert from a string

There are a few more issues like that needing fixing on other lines of the file.