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Input Issues when using do-while loop

Whenever input is outside of range 1-4 its supposed to throw an Invalid entry text and ask for another input, however when you type in another input, the program error's out and doesn't continue. I'm not sure where I am going wrong. I am using C# and this is an assignment that requires me to use the do while loop for this section.
static void Main(string[] args)
{
Write("Enter a salespersons name: ");
string salesPerson = ReadLine();
int intItem;
int intQuantity;
double item1 = 239.99;
double item2 = 129.75;
double item3 = 99.95;
double item4 = 350.89;
double dblItemSales;
double dblTotalSales;
do
{
Write("Enter an item number between 1 and 4 or -1 to quit: ");
intItem = Convert.ToInt32(ReadLine());
if ( intItem < 1 || intItem > 4 )
{
WriteLine("Invalid Entry");
Write("Enter an item number between 1 and 4 or -1 to quit: ");
intItem = Convert.ToInt32(ReadLine());
}
else if ( intItem == -1 )
{
WriteLine("Salesperson " + salesPerson + " sold a total of ");
break;
}
else
Write("Enter the quantity sold: ");
intQuantity = Convert.ToInt32(ReadLine());
}
while ( intItem != -1 );
WriteLine("Press Enter to Continue.");
ReadLine();
}

static void Main(string[] args)
{
Write("Enter a salespersons name: ");
string salesPerson = ReadLine();
int intItem;
int intQuantity;
double item1 = 239.99;
double item2 = 129.75;
double item3 = 99.95;
double item4 = 350.89;
double dblItemSales;
double dblTotalSales;
do
{
Write("Enter an item number between 1 and 4 or -1 to quit: ");
if (Int32.TryParse(ReadLine(), out intItem))
{
if (intItem == -1)
{
WriteLine("Salesperson " + salesPerson + " sold a total of ");
break;
}
else if (intItem < 1 || intItem > 4)
{
WriteLine("Invalid Entry");
}
else
{
Write("Enter the quantity sold: ");
if (!Int32.TryParse(ReadLine(), out intQuantity))
{
intQuantity = 0; // or whatever
}
}
}
}
while (intItem != -1);
WriteLine("Press Enter to Continue.");
ReadLine();
}

Since -1 < 1 it is the very first branch
if ( intItem < 1 || intItem > 4 ) // true when intItem == -1
{
...
}
else if ( intItem == -1 ) // this branch will never be executed
which runs. Put it like this:
while (true) { // keep looping until explicit quit
Write("Enter an item number between 1 and 4 or -1 to quit: ");
if (!int.TryParse(ReadLine(), out var intItem)) // what if user put "bla-bla-bla"?
Write("Syntax error. Integer 1..4 expected");
else if (intItem == -1) { // quit
WriteLine("Salesperson " + salesPerson + " sold a total of ");
break;
}
else if (intItem < 1 || intItem > 4) { // invalid range
WriteLine("Invalid Entry");
Write("Enter an item number between 1 and 4 or -1 to quit:");
}
else { // main routine
// intItem is integer in 1..4 range
Write("Enter the quantity sold: ");
//TODO: put relevant code here
}
}

You can try such thing, depending of what you want to do with quantities entered hence I put something for the sample:
bool isValid;
do
{
Console.Write("Enter an item number between 1 and 4 or -1 to end: ");
int.TryParse(Console.ReadLine(), out intItem);
if ( intItem == -1 ) break;
if ( intItem < 1 || intItem > 4 )
{
Console.WriteLine("Invalid entry: try again, please.");
continue;
}
dblItemSales++;
do
{
Console.Write("Enter the quantity sold: ");
isValid = int.TryParse(Console.ReadLine(), out intQuantity) && intQuantity >= 0;
if ( !isValid )
Console.WriteLine("Invalid entry: try again, please.");
}
while ( !isValid );
dblTotalSales += intQuantity;
}
while ( true );
Console.WriteLine($"Sales person {salesPerson} sold a total of {dblTotalSales}" +
$" for {dblItemSales} items");
Console.WriteLine("Press Enter to Continue.");
We use TryParse to ensure that a number is entered else it is 0 and the method rertuens false.

In case you don't want to change the current code. Short fix:
Move this intQuantity = Convert.ToInt32(Console.ReadLine()); line inside the else statement.
Delete this codes inside if statement:
Write("Enter an item number between 1 and 4 or -1 to quit: ");
intItem = Convert.ToInt32(ReadLine());
It should be look like this:
do
{
Console.Write("Enter an item number between 1 and 4 or -1 to quit:");
intItem = Convert.ToInt32(Console.ReadLine());
if (intItem< 1 || intItem> 4)
{
Console.WriteLine("Invalid Entry");
}
else if (intItem == -1)
{
Console.WriteLine("Salesperson " + salesPerson + " sold a total of ");
break;
}
else
{
Console.Write("Enter the quantity sold: ");
intQuantity = Convert.ToInt32(Console.ReadLine());
}
}
while (intItem != -1);
Console.WriteLine("Press Enter to Continue.");
Console.ReadLine();

How to put Pin in 4 digits only when entering a PIN and how to verified it?

I don't know the codes as I'm a beginner in c#, so could anyone help me with these? I want my pin to enter in 4 digits only and re verified the pin to continue in the menu?
{
class program
{
public static void Main()
{
int amount = 1000, deposit, withdraw;
int choice, pin = 0, x = 0;
Console.WriteLine("Enter Your Pin Number ");
pin = int.Parse(Console.ReadLine());
while (true)
{
Console.WriteLine("********Welcome to ATM Service**************\n");
Console.WriteLine("1. Check Balance\n");
Console.WriteLine("2. Withdraw Cash\n");
Console.WriteLine("3. Deposit Cash\n");
Console.WriteLine("4. Quit\n");
Console.WriteLine("*********************************************\n\n");
Console.WriteLine("Enter your choice: ");
choice = int.Parse(Console.ReadLine());
switch (choice)
{
case 1:
Console.WriteLine("\n YOUR BALANCE IN Rs : {0} ", amount);
break;
case 2:
Console.WriteLine("\n ENTER THE AMOUNT TO WITHDRAW: ");
withdraw = int.Parse(Console.ReadLine());
if (withdraw % 100 != 0)
{
Console.WriteLine("\n PLEASE ENTER THE AMOUNT IN MULTIPLES OF 100");
}
else if (withdraw > (amount - 500))
{
Console.WriteLine("\n INSUFFICENT BALANCE");
}
else
{
amount = amount - withdraw;
Console.WriteLine("\n\n PLEASE COLLECT CASH");
Console.WriteLine("\n YOUR CURRENT BALANCE IS {0}", amount);
}
break;
case 3:
Console.WriteLine("\n ENTER THE AMOUNT TO DEPOSIT");
deposit = int.Parse(Console.ReadLine());
amount = amount + deposit;
Console.WriteLine("YOUR BALANCE IS {0}", amount);
break;
case 4:
Console.WriteLine("\n THANK U USING ATM");
break;
}
}
Console.WriteLine("\n\n THANKS FOR USING OUT ATM SERVICE");
}
}
}

I suggest something like this:
// read size (4) digits
private static string ReadPin(int size = 4) {
StringBuilder sb = new StringBuilder(size);
while (sb.Length < size) {
var key = Console.ReadKey(true); // we don't want to show the secret pin on the screen
// Uncomment, if you want to let user escape entering the PIN
// if (key.Key == ConsoleKey.Escape) {
// return "";
// }
if (key.KeyChar >= '0' && key.KeyChar <= '9') {
sb.Append(key.KeyChar);
Console.Write('*'); // let's show * instead of actual digit
}
}
return sb.ToString();
}
...
// private: there's no need for Main to be public
private static void Main() {
...
Console.WriteLine("Enter Your Pin Number ");
int pin = int.Parse(ReadPin());
If you want to verify the given string (pin) which is expected to be of length size, you can try either Linq
using System.Linq;
...
string pin = ...
int size = 4;
bool isValidPin = pin.Length == size && pin.All(c => c >= '0' && c <= '9');
Or regular expressions:
using System.Text.RegularExpressions;
...
bool isValidPin = Regex.IsMatch(pin, $"^[0-9]{{{size}}}$");

int password;
int repassword
Do{
Console.WriteLine("\n Enter the password");
password= int.Parse(Console.ReadLine()); //first password
string ps = Convert.ToString(password);
}while(ps.Length!=4) //request the password if is not composed by 4 digits
//menu part//
Do{
Console.WriteLine("\n Reinsert the password");
repassword= int.Parse(Console.ReadLine()); //reinsert password
} while(repassword!=password)

c# code exits and re-executes when it shouldn't

My code works for the most part, I tried finding a solution online but struggled to find my exact issue. Here's the code, in C#:
static void Main(string[] args)
{
int maxFilm = 5;
int minFilm = 1;
Console.WriteLine("We are currently showing:");
Console.WriteLine("1. Rush");
Console.WriteLine("2. How I live now");
Console.WriteLine("3. Thor");
Console.WriteLine("4. Filth");
Console.WriteLine("5. Planes");
const int minAge1 = 15;
const int minAge2 = 12;
const int minAge3 = 18;
int filmNumber;
string filmNum;
int age;
string stringAge;
do
{
Console.WriteLine("Enter the number of the film you wish to see: ");
filmNum = Console.ReadLine();
filmNumber = Int32.Parse(filmNum);
if (filmNumber > maxFilm || filmNumber < minFilm)
{
Console.WriteLine("Invalid film number");
}
}
while (filmNumber > maxFilm || filmNumber < minFilm);
do
{
Console.WriteLine("Enter your age: ");
stringAge = Console.ReadLine();
age = Int32.Parse(stringAge);
if (age < 5 || age > 120)
{
Console.WriteLine("Invalid age");
}
} while (age < 5 || age > 120);
if (((filmNumber == 1 || filmNumber == 2) && age >= minAge1) || (filmNumber == 3 && age >= minAge2) || (filmNumber == 4 && age >= minAge3) || (filmNumber == 5))
{
Console.WriteLine("Enjoy the film");
}
else
{
Console.WriteLine("You are too young");
}
Input:
First, invalid movie number
Second, valid movie number
Third, age between 5-120
Expected output: Either "You are too young" or "enjoy the film" and then the code exits
What happens: The code exits and then re-executes from the start.
If I put a valid film number to start with, then it performs as expected. Any help is appreciated

After your final Console.WriteLine(), add a Console.ReadLine()
Example:
Console.WriteLine("Enjoy the film");
Console.ReadLine();
Also if you don't want the program to close after this, I suggest putting the program into a loop.

I assume that you want to see out put, so you can use following code :
Console.ReadLine();
or
Console.ReadKey();
To put entire code. generally, in loop is not good idea.

Invalid expression term 'else' after i typed it the second time

static void Main(string[] args)
{
Console.WriteLine("what is the value of 3 + 8?");
number = int.Parse(Console.ReadLine());
if (number == 11)
{
Console.WriteLine("well done");
Console.WriteLine("press enter once");
Console.ReadLine();
}
else;
{
Console.WriteLine("its 11 u idiot!!!");
Console.ReadLine();
}
Console.WriteLine("what is the value of 23132-23131?");
number = int.Parse(Console.ReadLine());
if (number == 1);
{
Console.WriteLine("oh yeah!");
Console.ReadLine();
}
else;
{
Console.WriteLine("u r such a noob!");
Console.ReadLine();
}
}
What is the problem there??? Visual studio told me invalid expression term 'else' after the second 'else' i typed and i don't know why?

Remove the semicolon after each of the two else keywords:
else // was else;
and after the if line:
if (number == 1) // was if (number == 1);
In addition, you should actually declare number:
var number = int.Parse(Console.ReadLine());
This is the final version of code that should work:
static void Main(string[] args)
{
Console.WriteLine("what is the value of 3 + 8?");
var number = int.Parse(Console.ReadLine());
if (number == 11)
{
Console.WriteLine("well done");
Console.WriteLine("press enter once");
Console.ReadLine();
}
else
{
Console.WriteLine("its 11 u idiot!!!");
Console.ReadLine();
}
Console.WriteLine("what is the value of 23132-23131?");
number = int.Parse(Console.ReadLine());
if (number == 1)
{
Console.WriteLine("oh yeah!");
Console.ReadLine();
}
else
{
Console.WriteLine("u r such a noob!");
Console.ReadLine();
}
}

Do it like this
int number;
Console.WriteLine("what is the value of 3 + 8?");
number = int.Parse(Console.ReadLine());
if (number == 11)
{
Console.WriteLine("well done");
Console.WriteLine("press enter once");
Console.ReadLine();
}
else
{
Console.WriteLine("its 11 u idiot!!!");
Console.ReadLine();
}
Console.WriteLine("what is the value of 23132-23131?");
number = int.Parse(Console.ReadLine());
if (number == 1)
{
Console.WriteLine("oh yeah!");
Console.ReadLine();
}
else
{
Console.WriteLine("u r such a noob!");
Console.ReadLine();
}

c#....my while loop keep repeating [duplicate]

This question already exists:
c# programming constructs - my while loop wont stop working when i want it to? [closed]
Closed 9 years ago.
i am trying to get my while loop to ONLY keep repeating till all subjects have been answered, then it should stop and display the bonus and final score. but don't know why its not doing that? help please.
namespace Assignment
{
class Class1
{
public static int attempt, sum, AptScore, GenScore, MathScore, EngScore, bonus, TotalScore, FinalScore, choice = 0;
public static string ans;
static void Main(string[] args)
{
bool stop = false;
Console.WriteLine("Welcome to this Salisbury University IQ Test game");
Console.WriteLine();
Console.WriteLine("How many times have you attempted this test?");
attempt = Convert.ToInt32(Console.ReadLine());
while (true)
if (attempt > 1)
{
Console.WriteLine("You cannot take this test");
}
else
{
Console.WriteLine(" \n1. Aptitude \n2. English. \n3. Math \n4. Gk \n5. Exit");
choice = Convert.ToInt32(Console.ReadLine());
switch (choice)
{
case 1:
Console.WriteLine(" What was the name of the lebanon tyrant who ruled for years unending before he was toppled due to civil war? \nA. Osama Bin laden \nB. Gaddafi \nC. Jonathan ");
ans = Console.ReadLine();
if (ans == "B" || ans == "b")
{
AptScore += 10;
}
break;
case 2:
Console.WriteLine(" What is the antonym of Pleasure? \nA. Pain \nB. Ecstacy \nC. Wonder");
ans = Console.ReadLine();
if (ans == "A" || ans == "a")
{
EngScore += 10;
}
break;
case 3:
Console.WriteLine(" What is the sum of 435 and 345? \nA. 799 \nB. 780 \nC. 600 ");
ans = Console.ReadLine();
if (ans == "B" || ans == "b")
{
MathScore += 10;
}
break;
case 4:
Console.WriteLine(" What year did Nigeria become a republic? \nA. 1960 \nB. 1963 \nC. 1990 ");
ans = Console.ReadLine();
if (ans == "B" || ans == "b")
{
GenScore += 10;
}
break;
case 5:
Environment.Exit(0);
break;
}
if (stop)
break;
TotalScore = MathScore + GenScore + EngScore + AptScore;
Console.WriteLine("Your total score is : " + TotalScore);
if (TotalScore == 10)
{
Console.WriteLine(" You have no Bonus point ");
}
else if (TotalScore == 20)
{
bonus += 2;
Console.WriteLine("Your Bonus is {0}", bonus);
}
else if (TotalScore == 30)
{
bonus += 5;
Console.WriteLine("Your Bonus is {0}", bonus);
}
else if (TotalScore == 40)
{
bonus += 10;
Console.WriteLine("Your Bonus is {0}", bonus);
}
else
{
FinalScore = TotalScore + bonus;
Console.WriteLine("Your finalscore is : " + FinalScore);
}
switch (FinalScore)
{
case 10:
if (FinalScore >= 10)
{
Console.WriteLine("Your IQ level is below average");
}
break;
case 22:
if (FinalScore >= 22)
{
Console.WriteLine("Your IQ level is average");
}
break;
case 35:
if (FinalScore >= 35)
{
Console.WriteLine("You are intelligent");
}
break;
case 40:
if (FinalScore == 40)
{
Console.WriteLine("You are a genius");
}
break;
default:
break;
}
}
}
}
}

if (stop)
break;
This never happens.

I see:
bool stop = false;
and also:
if (stop)
break;
But I never see a stop = true;
Where do you intend to set stop to true?