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C# C# Basics (Retired) Perfect Final

Johan Berg
PLUS
Johan Berg
Courses Plus Student 5,352 Points
Posted by Johan Berg
Johan Berg
Courses Plus Student 5,352 Points

C# Final Compilation Errors

When I try to compile my C# program, I receive the following error message:

  • "Program.cs(13,21): error CS0131: The left-hand side of an assignment must be a variable, a property or an indexer"
  • "Program.cs(25,32): error CS0019: Operator <' cannot be applied to operands of typeint' and `string'"

I have tried several times, but I have not been able to determine the source of this problem.

Program.cs 
using System;

namespace Treehouse.CodeChallenges
{
class Program
{
    static void Main()
    {
        while(true)
        {
            Console.Write("Enter the number of times to print \"Yay!\": ");
            var yay = Console.ReadLine();
            if (yay.ToLower()= "quit")
            {
                break;   
            }
            try{
                var run_time = int.Parse(yay);
                //var i = 0;
                if(run_time <= 0)
                {
                    Console.WriteLine("Enter a positive number!");
                    continue;
                }
                for(int x = 0; x < yay; x++)
                {
                    Console.WriteLine("Yay!");   
                }

            }
            catch (FormatException)
            {
                Console.WriteLine("Not a valid number.");
                continue;
            }

        }
    }
}
}

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

"Program.cs(13,21): error CS0131: The left-hand side of an assignment must be a variable, a property or an indexer"

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

You probably intended a comparison ("==") there instead of an assignment.

"Program.cs(25,32): error CS0019: Operator <' cannot be applied to operands of typeint' and `string'"

                for(int x = 0; x < yay; x++)

The variable "x" is an int, but "yay" contains a string. Did you mean to compare "x" with "run_time" instead?

Also be aware that a program that follows the challenge instructions will only ask for input one time, and either print "Yay!"s or an error message. But either way it should end.

Johan Berg
Johan Berg
Courses Plus Student 5,352 Points
Johan Berg
Johan Berg
Courses Plus Student 5,352 Points

I managed to solve the "The left-hand side of an assignment must be a variable, a property or an indexer" problem by doing what you suggested, but when I replaced the "yay" variable in the for loop with "run_time", I received the following error message:

"System.NullReferenceException: Object reference not set to an instance of an object at Treehouse.CodeChallenges.Program.Main () [0x00010] in <7e87a22d2c3d4d709e9df60edcfbb43b>:0 at MonoTester.Run () [0x000b5] in MonoTester.cs:91 at MonoTester.Main (System.String[] args) [0x00013] in MonoTester.cs:28"

I have not changed anything else aside from those two aforementioned parts of the program.

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

Don't overlook the third suggestion. You still have an outer loop that prevents the program from ending until "quit" is entered. This is not part of the instructions.