string tastetryk;
ConsoleKeyInfo tast;
Console.ForegroundColor = ConsoleColor.White;
Console.BackgroundColor = ConsoleColor.Blue;
Console.Clear();
do
{
Console.WriteLine("Menu");
Console.WriteLine(" ");
Console.WriteLine("Tryk en tast for at vælge funktion");
Console.WriteLine(" ");
Console.WriteLine("I - Beregn strøm");
Console.WriteLine("U - Spænding");
Console.WriteLine("R - Modstand");
Console.WriteLine(" ");
Console.WriteLine("(Esc) for at slutte ");
tast = Console.ReadKey();
tastetryk = tast.Key.ToString();
Console.Clear();
switch(tastetryk)
{
case "I":
Console.WriteLine("du har tastet I");
Console.Write("Tast Q for at komme tilbage");
tast = Console.ReadKey();
break;
case "U":
Console.WriteLine("du har tastet U");
Console.Write("Tast Q for at komme tilbage");
tast = Console.ReadKey();
break;
case "R":
Console.WriteLine("du har tastet R");
Console.Write("Tast Q for at komme tilbage");
tast = Console.ReadKey();
break;
default:
Console.WriteLine("forkert tast");
Thread.Sleep(1000);
Console.Clear();
break;
}
}
while (tast.Key == ConsoleKey.Q);
I made this code for a Menu, when i press I, U or R, one of the case will come true, when you press Q it will return to main menu. My problem is when default is true, i want it to loop to main menu without any need to press Q, I tried with tast = Consolekey.Q
Sorry for my really bad english
Clearly, you cannot break from the loop since the break breaks from the switch statement, as you've surely noticed.
Two simple solutions :
First, add a boolean flag indicating you should exit the loop, adding a new condition in the while statement.
bool bExit = false;
do
{
switch
{
/*
code here
*/
default:
bExit = true;
//etc.
}
}
while(tast.Key == ConsoleKey.Q || !bExit)
Now, I know thid could be considered pure evil but... have you considered using a goto?
do
{
switch
{
/*
code here
*/
default:
goto outOfLoop;
}
}
while(tast.Key == ConsoleKey.Q)
outOfLoop:
// etc.
I believe the second solution is actually cleaner but people could react violently to goto statements.
Related
i'm very new to C# (well, programming in general)
I am trying to create a menu for a c# console application. The the menu keeps reappearing after a selection from the menu is made... I've researched and tried many different options but nothing seems to be working for me.... I know it's something stupid that I've done incorrectly.
Any advice or guidance would be very much appreciated. Thanks in advanced.
static void Main() //Start of program
{
//Menu and other UI stuff
int userSelection = 0;
do
{
Console.WriteLine("[1] Encryption");
Console.WriteLine("[2] Decryption");
Console.WriteLine("[3] Exit");
Console.Write ("Please choose an option 1-3: ");
userSelection = Int32.Parse(Console.ReadLine());
switch(userSelection)
{
case 1:
readFile();
break;
case 2:
decryption();
break;
case 3:
Environment.Exit(0);
break;
default:
Console.WriteLine("Your selection is invalid. Please try again.");
break;
}
}
while (userSelection != 4);
}
Your do/while only will stops when your userSelection have value 4, in this example, it never will happen.
change your while condition to
while(userSelection <= 0 || userSelection > 3)
it should solve...
maybe you would like to use something like:
int userSelection = 0;
bool validAnswer = false;
do
{
Console.WriteLine("[1] Encryption");
Console.WriteLine("[2] Decryption");
Console.WriteLine("[3] Exit");
Console.Write ("Please choose an option 1-3: ");
userSelection = Int32.Parse(Console.ReadLine());
switch(userSelection)
{
case 1:
readFile();
validAnswer = true;
break;
case 2:
decryption();
validAnswer = true;
break;
case 3:
validAnswer = true;
Environment.Exit(0);
break;
default:
Console.Clear();
Console.WriteLine("Your selection is invalid. Please try again.");
break;
}
}while (!validAnswer);
It keeps reappearing because you placed your code in a do while loop. If you want to run this code only once don't use looping constructs, just place it directly in Main.
If you use something like
do
{
// ...
}
while (userSelection != 4);
the code inside the loop will be repeated until the user enters 4.
From msdn article on a do while:
The do statement executes a statement or a block of statements
repeatedly until a specified expression evaluates to false.
Another option would be to use a break statement after the switch block.
class Program
{
static void Main() //Start of program
{
//Menu and other UI stuff
string userSelection;
do
{
Console.Clear();
Console.WriteLine("[1] Encryption");
Console.WriteLine("[2] Decryption");
Console.WriteLine("[3] Exit");
Console.Write("Please choose an option 1-3: ");
userSelection = Console.ReadLine();
switch (userSelection)
{
case "1":
Console.WriteLine("mission 1");
break;
case "2":
Console.WriteLine("mission 2");
break;
case "3":
Environment.Exit(0);
break;
default:
Console.WriteLine("Your selection is invalid. Please try again.");
break;
}
Console.ReadLine();
}
while (true);
}
}
I have looked really hard on this. Integers seem easy, but this is what I have been trying to figure out in C# in visual studio.
I want to have a user input of a letter like "a" then the console writes "apple", b=bobby, c=charlie, etc. and when they don't put a letter then it gives an error message like "no letters used". I am not sure if I am suppose to convert the user input from a string with ToChar or what the best way to do this is. I haven't gotten into arrays yet and haven't figured out the switch command with characters (instead of integers or strings).
This is how I was trying to do it:
Console.WriteLine("Enter a letter ");
choice = Convert.ToChar(Console.ReadLine());
if (char choice = 'a'){
Console.WriteLine("apple");
}else if (char choice = 'b'{
Console.WriteLine("bobby");
}else if (char choice = 'b'{
Console.WriteLine("bobby");
}else (char choise=!IsLetter){
Console.WriteLine("No Letters entered");
If you want to stick to if else, here is what you can do:
if (choice == 'a')
{
Console.WriteLine("apple");
}
else if (choice =='b')
{
Console.WriteLine("bobby");
}
else if (char choice = 'c')
{
Console.WriteLine("charlie");
}
else
{
Console.WriteLine("No Letters entered");
}
You don't need to put condition on your else anymore :)
Use a switch statement, probably best for your scenario
static void Main(string[] args)
{
//initialise bool for loop
bool flag = false;
//While loop to loop Menu
while (!flag)
{
Console.WriteLine("Menu Selection");
Console.WriteLine("Press 'a' for apple");
Console.WriteLine("Press 'b' for bobby");
Console.WriteLine("Type 'exit' to exit");
//Read userinput
//Store inside string variable
string menuOption = Console.ReadLine();
switch (menuOption)
{
case "a":
//Clears console for improved readability
Console.Clear();
//"\n" Creates empty line after statement
Console.WriteLine("apple has been selected\n");
//Break out of switch
break;
case "b":
Console.Clear();
Console.WriteLine("bobby has been selected\n");
break;
case "exit":
Console.Clear();
Console.WriteLine("You will now exit the console");
//bool set to false to exit out of loop
flag = true;
break;
//Catch incorrect characters with default
default:
Console.Clear();
//Error message
Console.WriteLine("You have not selected an option\nPlease try again\n\n");
break;
}
}
Console.ReadLine();
This is how you write it using a switch:
switch (choice){
case 'a':
Console.WriteLine("apple");
break;
case 'b':
Console.WriteLine("bobby");
break;
case 'c':
Console.WriteLine("charlie");
break;
default:
Console.WriteLine("No Letters entered");
break;
}
I'm new to c# and I'm creating a little console application. I want a smooth menu system changing on key inputs. I have a loop registering
public void MainMenu()
{
ConsoleKeyInfo _key;
do
{
Console.WriteLine("Main Menu");
Console.WriteLine("Press 1 for cars");
Console.WriteLine("Press 2 for planes");
Console.WriteLine("Press 3 for boats");
Console.WriteLine("Enter 'q' to exit");
_key = Console.ReadKey();
switch ((char)_key.Key)
{
case '1':
{
Console.Clear();
CarMenu();
break;
}
case '2':
{
Console.Clear();
PlaneMenu();
break;
}
case '3':
{
Console.Clear();
BoatMenu();
break;
}
case 'Q':
{
Environment.Exit(0);
break;
}
default:
{
Console.WriteLine("No options to that key...");
Console.WriteLine("-------------------------\n\n");
break;
}
}
} while (true);
}
public void CarMenu()
{
do
{
Console.Clear();
Console.WriteLine("Car menu");
Console.WriteLine("Press 1 to list all cars");
Console.WriteLine("Press 2 to list single car");
Console.WriteLine("Press 3 to register a new car");
Console.WriteLine("Press 0 for main menu");
Console.WriteLine("Enter 'q' to exit");
_key = Console.ReadKey();
Console.WriteLine((char)_key.Key);
Console.ReadKey();
switch ((char)_key.Key)
{
case '1':
{
Console.Clear();
_handler.listAllDevices();
break;
}
case '2':
{
Console.Clear();
PlaneMenu();
break;
}
case '3':
{
Console.Clear();
BoatMenu();
break;
}
case '0':
{
Console.Clear();
MainMenu();
break;
}
case 'Q':
{
Environment.Exit(0);
break;
}
default:
{
Console.WriteLine("No options to that key...");
Console.WriteLine("-------------------------\n\n");
break;
}
}
} while (true);
}
I have several cases, amongst case '1' and case 'Q'. First time I press any of them it works but next time I need to press 1 twice and q thrice. No matter SHIFT + q or Caps Lock. I tried a number of different solutions, clearing buffers etc but haven't really accomplished much.
Seems strange to me but I guess I'm missing something. Any clues? Thanks
So the full snippet is:
{
private static void Main(string[] args)
{
do
{
Console.WriteLine("Main Menu");
Console.WriteLine("Press 1 for cars");
Console.WriteLine("Press 2 for planes");
Console.WriteLine("Press 3 for boats");
Console.WriteLine("Enter 'q' to exit");
ConsoleKeyInfo _key = Console.ReadKey();
switch ((char) _key.Key)
{
case '1':
{
Console.Clear();
CarMenu();
break;
}
case '2':
{
Console.Clear();
//PlaneMenu();
break;
}
case '3':
{
Console.Clear();
//BoatMenu();
break;
}
case 'Q':
{
Environment.Exit(0);
break;
}
default:
{
Console.WriteLine("No options to that key...");
Console.WriteLine("-------------------------\n\n");
break;
}
}
} while (true);
}
public static void CarMenu()
{
do
{
Console.Clear();
Console.WriteLine("Car menu");
Console.WriteLine("Press 1 to list all cars");
Console.WriteLine("Press 2 to list single car");
Console.WriteLine("Press 3 to register a new car");
Console.WriteLine("Press 0 for main menu");
Console.WriteLine("Enter 'q' to exit");
ConsoleKeyInfo _key = Console.ReadKey();
Console.WriteLine((char) _key.Key);
//Console.ReadKey();
switch ((char) _key.Key)
{
case '1':
{
Console.Clear();
Console.WriteLine("1");
//_handler.listAllDevices();
break;
}
case '2':
{
Console.Clear();
Console.WriteLine("1");
break;
}
case '3':
{
Console.Clear();
Console.WriteLine("1");
break;
}
case '0':
{
Console.Clear();
return;
}
case 'Q':
{
Environment.Exit(0);
return;
}
default:
{
Console.WriteLine("No options to that key...");
Console.WriteLine("-------------------------\n\n");
break;
}
}
} while (true);
}
}
As you can see, I have coomented second call to ReadKey(). This was original problem.
I need to return back to the beginning of the code shown here after a user enters the wrong key. Is there any simple line of code that will just return back to another line? As you can see I already have an if statement set up so I can just add something that can return back to the beginning or to another area in my code. I am really quite new to c# and programming in general. I really just don't want to have to enter all the code again into another if statement that would produce the same issue. I would preferably like to have the code just run again after a user enters a wrong key, because then they can re-read it without having to start from scratch again.
//Runs battle interactive
Console.WriteLine("");
Console.WriteLine("You have encountered a simple guard! He deals 2 damage per attack and has 1 HP.");
Console.WriteLine("You currently have: " + Program.Inventory);
Console.WriteLine("Choose a weapon!");
var input2 = Console.ReadKey();
//Key checker for items
switch (input2.Key)
{
case ConsoleKey.D1:
Console.WriteLine("");
if (Items.iniFists == true)
{
Console.WriteLine("You have attacked with your Fists for 1 DMG!");
}
else
{
//this will never run, just a placeholder
Console.WriteLine("You Don't have your fists!");
switch (input2.Key)
{
case ConsoleKey.D1:
Console.WriteLine("");
if (Items.iniFists == true)
{
Console.WriteLine("You have attacked with your Fists for 1 DMG!");
}
else
{
//this will never run, just a placeholder
Console.WriteLine("You Don't have your fists!");
}
break;
case ConsoleKey.D2:
Console.WriteLine("");
if (Items.iniLongsword == true)
{
Console.WriteLine("You have chosen to attack with the Longsword for 2 DMG!");
}
else
{
Console.WriteLine("You don't have a longsword!");
}
break;
case ConsoleKey.D3:
Console.WriteLine("");
if (Items.iniBow == true)
{
Console.WriteLine("You have chosen to attack with the Bow for 3 DMG!");
}
else
{
Console.WriteLine("You don't have a Bow!");
}
break;
case ConsoleKey.D4:
Console.WriteLine("");
if (Items.iniLightstaff == true)
{
Console.WriteLine("You have chosen to attack with the Lightstaff for 4 DMG!");
}
else
{
Console.WriteLine("You don't have a Lightstaff!");
}
break;
case ConsoleKey.D5:
Console.WriteLine("");
Console.WriteLine("You can't attack with an Apple!");
break;
case ConsoleKey.D6:
Console.WriteLine("");
Console.WriteLine("You can't attack with a Golden Key!");
break;
case ConsoleKey.D7:
Console.WriteLine("");
Console.WriteLine("You can't attack with a Steak!");
break;
}
}
break;
case ConsoleKey.D2:
Console.WriteLine("");
if (Items.iniLongsword == true)
{
Console.WriteLine("You have chosen to attack with the Longsword for 2 DMG!");
}
else
{
Console.WriteLine("You don't have a longsword!");
}
break;
case ConsoleKey.D3:
Console.WriteLine("");
if (Items.iniBow == true)
{
Console.WriteLine("You have chosen to attack with the Bow for 3 DMG!");
}
else
{
Console.WriteLine("You don't have a Bow!");
}
break;
case ConsoleKey.D4:
Console.WriteLine("");
if (Items.iniLightstaff == true)
{
Console.WriteLine("You have chosen to attack with the Lightstaff for 4 DMG!");
}
else
{
Console.WriteLine("You don't have a Lightstaff!");
}
break;
case ConsoleKey.D5:
Console.WriteLine("");
Console.WriteLine("You can't attack with an Apple!");
break;
case ConsoleKey.D6:
Console.WriteLine("");
Console.WriteLine("You can't attack with a Golden Key!");
break;
case ConsoleKey.D7:
Console.WriteLine("");
Console.WriteLine("You can't attack with a Steak!");
break;
}
C# supports labels in code, however it is not recommended due to the fact that it violates many coding best practices, but I guess there is always an exception to any rule.
class Program
{
static void Main(string[] args)
{
Start:
Console.WriteLine("Start Here... Press any key");
var key = Console.ReadKey(true);
switch (key.Key)
{
case ConsoleKey.A:
goto MyLabel;
case ConsoleKey.B:
goto MyLabel2;
case ConsoleKey.C:
goto MyLabel3;
default:
Console.WriteLine("Bad Choice");
goto Start;
}
MyLabel:
Console.WriteLine("MyLabel: A");
goto Start;
MyLabel2:
Console.WriteLine("MyLabel: B");
goto Start;
MyLabel3:
Console.WriteLine("MyLabel: C");
goto Start;
}
}
You can find more information here:
http://msdn.microsoft.com/en-us/library/d96yfwee.aspx
http://msdn.microsoft.com/en-us/library/13940fs2.aspx
you have a couple options, you can use a while loop
bool continue = true;
while(continue == true)// or you can simply type "while(continue)"
{
/* everything inside the `while` loop will be
repeated until `continue` is not `true`. */
}
you can also use methods
public static void doStuff()
{
// insert stuff here
}
and then you can call that from elsewhere in your class
if(x = 6)
{
doStuff(); //this line does the stuff
doStuff(); // this line does the stuff again.
}
One answer to this is to check that you have valid input in a loop like this:
while (true)
{
ConsoleKey i = Console.ReadKey()
if (i == ConsoleKey.D1 || ... ) //Check if it's equal to any valid key, you
//might be able to simplify it with <= and
//>= if valid keys are sequential.
break;
Console.WriteLine("You have entered an invalid key");
}
Alternatively, you can add a goto statement at the end of your switch block:
SwitchStatement: switch(input2.Key)
...
default:
Console.WriteLine("Invalid key pressed");
goto SwitchStatement;
break;
}
Here is an example where a menu of values is available. i would like to have it loop back to the start if none of the options are chosen.
static void Main(string[] args)
{
Console.WriteLine("1 : Option 1");
Console.WriteLine("2 : Option 2");
Console.WriteLine("3 : Option 3");
Console.WriteLine("4 : Option 4");
Console.WriteLine("5 : Option 5");
Console.Write("Please enter your option choice: ");
string choice = Console.ReadLine();
int intChoice = int.Parse(choice);
switch (intChoice)
{
case 1:
Console.WriteLine("you chose 1");
break;
case 2:
Console.WriteLine("you chose 2");
break;
case 3:
Console.WriteLine("you chose 3");
break;
case 4:
Console.WriteLine("you chose 4");
break;
case 5:
Console.WriteLine("you chose 5");
break;
}
}
I've tried to do it through using classes and method, but i just got really confused.
thank you in advance for any help.
Wrap the whole thing in a do-while block:
bool isValid = true;
do
{
isValid = true;
// Write to console
// read from console
switch(intChoice)
{
// Place some cases here.
default:
Console.WriteLine("Invalid Choice")
isValid = false;
}
}
while(!isValid);
Use a boolean value as a flipswitch that tell the while loop to continue running or not. Here's a small example:
bool stillRunning = true;
while (stillRunning)
{
Console.WriteLine("Enter a number.");
string input = Console.ReadLine();
int key = Convert.ToInt32(input);
switch (key)
{
case 1:
// Do something.
stillRunning = false;
break;
case 2:
// Do something.
stillRunning = false;
break;
default:
Console.WriteLine("No key selected.");
break;
}
}
you can use default
switch (intChoice)
{
case 1:
Console.WriteLine("you chose 1");
break;
case 2:
Console.WriteLine("you chose 2");
break;
.......
default:
//your logic here
break;
}
it is your choice after that how you like to do it. you can use a while and a Boolean value like this:
static void Main(string[] args)
{
Console.WriteLine("1 : Option 1");
Console.WriteLine("2 : Option 2");
Console.WriteLine("3 : Option 3");
Console.WriteLine("4 : Option 4");
Console.WriteLine("5 : Option 5");
Console.Write("Please enter your option choice: ");
bool correct = true;
while (correct)
{
string choice = Console.ReadLine();
int intChoice = int.Parse(choice);
switch (intChoice)
{
case 1:
Console.WriteLine("you chose 1");
break;
case 2:
Console.WriteLine("you chose 2");
break;
case 3:
Console.WriteLine("you chose 3");
break;
case 4:
Console.WriteLine("you chose 4");
break;
case 5:
Console.WriteLine("you chose 5");
break;
default:
correct = false;
break;
}
}
}
Thus you need only one number, it's better to use GetKey method, then reading string value from console and then parsing it to int:
DisplayOptions();
bool choiceDone;
do
{
choiceDone = true;
switch(GetChoice())
{
case ConsoleKey.D1:
Console.WriteLine("you chose 1");
break;
case ConsoleKey.D2:
Console.WriteLine("you chose 2");
break;
// etc
default:
choiceDone = false;
break;
}
} while(!choiceDone);
Also I have extracted several methods, to make code more clean:
private ConsoleKey GetChoice()
{
Console.Write("Please enter your option choice: ");
return Console.ReadKey().Key;
}
private void DisplayOptions()
{
Console.Clear();
Console.WriteLine("1 : Option 1");
Console.WriteLine("2 : Option 2");
Console.WriteLine("3 : Option 3");
Console.WriteLine("4 : Option 4");
Console.WriteLine("5 : Option 5");
}
public void GetInput()
{
int inputValue = 0;
bool isValidInput = false;
List<int> validEntries = new List<int> { 1,2,3, 42, 55, 69};
while (!isValidInput)
isValidInput = int.TryParse(Console.ReadLine(), out inputValue) && validEntries.Contains(inputValue);
switch (inputValue)
{
case 1:
{
// something
break;
}
case 2:
{
// something else
break;
}
default:
{
//yet something else
break;
}
}
}
Edit: Added explicit value check instead of accepting any integer.
The most obvious solution seems to be:
bool loop = true;
while (loop)
{
loop = false;
switch (Console.ReadLine())
{
case "1":
Console.WriteLine("you chose 1");
break;
case "2":
Console.WriteLine("you chose 2");
break;
case "3":
Console.WriteLine("you chose 3");
break;
case "4":
Console.WriteLine("you chose 4");
break;
case "5":
Console.WriteLine("you chose 5");
break;
default:
loop = true;
break;
}
}
There could be a better way to do this though.