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How do I make my C# program start again from the top after every time it finishes

guys, I'm a beginner at this, after trying to build this calculator I just wanted to learn how to make it start again I tried using a while loop but unfortunately, I wasn't able to figure it out please help thanks.
using System;
namespace ConsoleApp
{
class Program
{
static void Main(string[] args)
{
Console.Write("Enter a number");
double num1 = Convert.ToDouble(Console.ReadLine());
Console.Write("Add an operator");
string op = Console.ReadLine();
Console.Write("Enter another number");
double num2 = Convert.ToDouble(Console.ReadLine());
if (op == "+")
{
Console.WriteLine(num1 + num2);
}
else if (op == "-")
{
Console.WriteLine(num1 - num2);
}
else if (op == "/")
{
Console.WriteLine(num1 / num2);
}
else if (op == "*")
{
Console.WriteLine(num1 * num2);
}
else
{
Console.WriteLine("Invalid operator");
}
}
}
}

To keep it running, you can add a while(true) to wrap your logic code. this will repeatedly execute the block of code. In case there is a condition where you want to exit the loop, you can achieve this via break
static void Main(string[] args)
{
while (true){
Console.Write("Enter a number");
double num1 = Convert.ToDouble(Console.ReadLine());
Console.Write("Add an operator");
string op = Console.ReadLine();
Console.Write("Enter another number");
double num2 = Convert.ToDouble(Console.ReadLine());
if (op == "+")
{
Console.WriteLine(num1 + num2);
}
else if (op == "-")
{
Console.WriteLine(num1 - num2);
}
else if (op == "/")
{
Console.WriteLine(num1 / num2);
}
else if (op == "*")
{
Console.WriteLine(num1 * num2);
}
else
{
Console.WriteLine("Invalid operator");
}
if (//condition is ok and you want to break out of the loop){
break;
}
}
}

If it is console application,
you could do something like this at the end of your app -
System.Diagnostics.Process.Start("your_prog_name.exe"); Environment.Exit(0);
It should terminate previous process and start it again.
Console window won't disappear.

I Can't call the methods in C# am using [closed]

Closed. This question is not reproducible or was caused by typos. It is not currently accepting answers.
This question was caused by a typo or a problem that can no longer be reproduced. While similar questions may be on-topic here, this one was resolved in a way less likely to help future readers.
Closed 1 year ago.
Improve this question
This is my code
Basic Calculator Using 2 methods
1 is the main method
2 is the operator
namespace ConsoleApp1
{
class Program
{
static void Main(string[] args)
{
int num1;
int num2; //Variables for equation
string op;
//int Answer;
Console.Write("Enter the first number : ");
num1 = Convert.ToInt32(Console.ReadLine());
//User input for equation
Console.Write("Now enter your second number : ");
num2 = Convert.ToInt32(Console.ReadLine());
Console.Write("Ok now enter your operation ( x , / , +, -) ");
op = Console.ReadLine();
Methods1(); // This is the error, The error says
// There's no argumen given that corresponds
}
static int Methods1(int num1, int num2, string op)
{
if (op == "+")
{
return num1 + num2;
}
else if (op == "-")
{
return num1 - num2;
}
else if (op == "/")
{
return num1 / num2;
}
else if (op == "*")
{
return num1 * num2;
}
else
{
Console.WriteLine("Invalid Operator");
return 0;
}
}
}
}

You have called the Methods1() method without arguments. Change the code to the following:
using System;
namespace Test_app_1
{
class Program
{
static void Main(string[] args)
{
int num1;
int num2; //Variables for equation
string op;
int Answer;
Console.Write("Enter the first number : ");
num1 = Convert.ToInt32(Console.ReadLine());
//User input for equation
Console.Write("Now enter your second number : ");
num2 = Convert.ToInt32(Console.ReadLine());
Console.Write("Ok now enter your operation ( * , / , +, -) ");
op = Console.ReadLine();
Answer = Methods1(num1, num2, op); // Now no error...
Console.WriteLine(Answer + "\nPress any key to exit..."); //You forgot to add Console.Writeline
Console.Read(); //Also forgot Console.Read
}
static int Methods1(int num1, int num2, string op)
{
if (op == "+")
{
return num1 + num2;
}
else if (op == "-")
{
return num1 - num2;
}
else if (op == "/")
{
return num1 / num2;
}
else if (op == "*")
{
return num1 * num2;
}
else
{
Console.WriteLine("Invalid Operator");
return 0;
}
}
}
}

Why isn't the char changing the way I Intend it too?

I am new here so please excuse me for the poor formatting,
I wrote a simple calculator in c# but it seems my multiplication and division are not working correctly.
when running the code it works fine until I try to output the answer and then it outputs "Error, Unknown operator" which is what I told it to output when it doesn't identify the operator stored in the operation variable.
here is the code (sorry for dumping so much code, I am not sure what is relevant and what is not):
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleApp1
{
class MainClass
{
public static void Main(string[] args) // method called "main", when the program starts, this runs
{
start:
// variable declarations
double Num1;
double Num2;
int operationId;
string operationName = "1";
string operationName2 = "1";
Char operation;
double answer;
// choosing an operator
Console.WriteLine("select an operation from the list and type it's associated number:");
Console.WriteLine("1 - sum \n" + "2 - subtraction \n" + "3 - division\n" + "4 - multipication \n");
operationId = Convert.ToInt32(Console.ReadLine());
// checking which operation has been chosen
if (operationId == 1)
{
operationName = "added to";
operationName2 = "added";
operation = '+';
} else if (operationId == 2)
{
operationName = "subtracted from";
operationName2 = "subtracted";
operation = '-';
} else if (operationId == 3)
{
operationName = "divided";
operationName2 = "divided by";
operation = '/';
} else if (operationId == 4)
{
operationName = "multiplied";
operationName2 = "multiplied by";
operation = '*';
} else
{
Console.WriteLine("Invalid option");
goto start;
}
// receving user input
Console.WriteLine("Insert a number to be " + operationName + ":");
Num1 = Convert.ToDouble (Console.ReadLine());
Console.WriteLine("Insert a number to be " + operationName2);
Num2 = Convert.ToDouble(Console.ReadLine());
//calculating answer
if (operation == '+')
{
answer = Num1 + Num2;
}
else if (operation == '-')
{
answer = Num1 - Num2;
}
else if (operationId == '/')
{
answer = Num1 / Num2;
}
else if (operationId == '*')
{
answer = Num1 + Num2;
} else
{
answer = 0000;
Console.WriteLine("Error, Unknown operator \n");
goto start;
}
Console.WriteLine();
Console.WriteLine("The result is:");
Console.WriteLine(answer);
Console.ReadKey();
Console.WriteLine();
goto start;
}
}
}

Your first 2 ifs check operation, the second 2 check operationId. Change the multiply and divide ones to also check operation.
//...
else if (operation == '/')
{
answer = Num1 / Num2;
}
else if (operation == '*')
{
answer = Num1 * Num2; //<-- Change to this from Num1 + Num2
}
//...
And by the way, your multiply block is adding the numbers, not multiplying. I've fixed that in my block above.

I guess the problem is with - 2 conditions are checking operation and 2 conditions are checking operationId. Perhaps you may want to change all the checks to be either with operation or with operationId.
if (operation == '+')
{
answer = Num1 + Num2;
}
else if (operation == '-')
{
answer = Num1 - Num2;
}
else if (operationId == '/')
{
answer = Num1 / Num2;
}
else if (operationId == '*')
{
answer = Num1 + Num2;
} else
{
answer = 0000;
Console.WriteLine("Error, Unknown operator \n");
goto start;
}

goto - not within scope (C#)

I am very new to code. Can anyone in a simple way explain why I cant use the goto statement like this, to make the code start over again? Or, how this could have been done in the correct way? And also, why I get an error message on the use of "static".
**
"No such label "Start" within the scope of the goto statmenet"
"The modifier static is not valid for this item"
using System;
namespace ConsoleApp3
{
class Program
{
static void Main(string[] args)
{
Start:
Random numberGenerator = new Random();
int num1 = numberGenerator.Next(1,11);
int num2 = numberGenerator.Next(1, 4);
Console.WriteLine("What is " + num1 + " times " + num2 + "?");
int svar = Convert.ToInt32(Console.ReadLine());
if (svar == num1 * num2)
{
Console.WriteLine("well done!");
}
else
{
int responseIndex = numberGenerator.Next(1, 4);
switch (responseIndex)
{
case 1:
Console.WriteLine("Wrong, try again? [Y or N]");
AskUser();
break;
case 2:
Console.WriteLine("The answer was incorrect");
AskUser();
break;
default:
Console.WriteLine("You can do better than that");
AskUser();
break;
}
static void AskUser() {
string jaellernei = Console.ReadLine().ToUpper();
if (jaellernei == "Y")
{
goto Start;
} else
{
return;
} }
}
}
}
}

Firstly, your AskUser method is incorrectly nested inside the other method - move it out.
Secondly: goto is only valid within a single method; you can jump around a single stack frame - you cannot jump between stack frames.
Thirdly: the number of times you should be using goto... well, it isn't quite zero, but it asymptotically approaches zero.

Don't use goto unless you MUST to !
and As #Marc Gravell said, it's valid within a single method.
Alternatively : you can make a method of the code u used in the Main method, and then call it from both, main method and the other method where you used goto statement.
Like :
using System;
namespace ConsoleApp3
{
class Program
{
static void Main(string[] args)
{
someFunction();
}
static void someFunction()
{
Random numberGenerator = new Random();
int num1 = numberGenerator.Next(1, 11);
int num2 = numberGenerator.Next(1, 4);
Console.WriteLine("What is " + num1 + " times " + num2 + "?");
int svar = Convert.ToInt32(Console.ReadLine());
if (svar == num1 * num2)
{
Console.WriteLine("well done!");
}
else
{
int responseIndex = numberGenerator.Next(1, 4);
switch (responseIndex)
{
case 1:
Console.WriteLine("Wrong, try again? [Y or N]");
AskUser();
break;
case 2:
Console.WriteLine("The answer was incorrect");
AskUser();
break;
default:
Console.WriteLine("You can do better than that");
AskUser();
break;
}
}
}
static void AskUser()
{
string jaellernei = Console.ReadLine().ToUpper();
if (jaellernei == "Y")
{
someFunction();
}
else
{
return;
}
}
}
}

You could do it like this
public static Random randd = new Random();
public static void FlachCards()
{
Start:
if (AskAUser() == "Y")
{
goto Start;
}
}
public static String AskAUser()
{
Console.WriteLine("Enter Y to play again");
return Console.ReadLine();
}

Return to Start/Top in C # console application

I am trying to go back to start in c# console program, and i am somehow able to do it, but the problem is that i am not able to do it using the Y/N statement. mean if i type the Y (yes) from keyboard then the program start from it's starting (beginning) point if i type N then it will terminate the program.
My Console code is:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace simple_calculation
{
class Program
{
static void Main(string[] args)
{
bool bktop = true;
string option;
while (bktop)
{
Console.WriteLine("Please enter the values");
int val = int.Parse(Console.ReadLine());
int val1 = int.Parse(Console.ReadLine());
int res = val + val1;
int red = val / val1;
Console.WriteLine("Please enter the operator");
string oper=Console.ReadLine();
if (oper == "+")
{
Console.WriteLine("sum is:" + res);
}
else if (oper == "/")
{
Console.WriteLine("division is:" + red);
}
else
{
Console.WriteLine("do you want to continue? enter Y/N");
option = Console.ReadLine();
if(option=="Y")
{
bktop = false;
}
else
{
bktop = true;
}
}
Console.ReadLine();
}
}
}
}
What I want: i want that when the program reaches to the else condition then there is a text appear in the console "do you want to continue? enter Y/N" if the user enter Y then the program start again and if the user enter N then the program will terminate.
Any help will be appreciated.

class Program
{
static void Main(string[] args)
{
// Change 1
bool bktop = true;
string option;
while (bktop)
{
bktop = true;
Console.WriteLine("Please enter the values");
int val = int.Parse(Console.ReadLine());
int val1 = int.Parse(Console.ReadLine());
int res = val + val1;
int red = val / val1;
Console.WriteLine("Please enter the operator");
string oper = Console.ReadLine();
if (oper == "+")
{
Console.WriteLine("sum is:" + res);
}
else if (oper == "/")
{
Console.WriteLine("division is:" + red);
}
else
{
Console.WriteLine("do you want to continue? enter Y/N");
option = Console.ReadLine();
// Change 2
if (option.ToUpper() != "Y")
{
bktop = false;
}
}
}
}
}