I'm new to C# and was wondering, if I wanted to close my app by pressing the Enter button how would I do so? After doing some research on this website the closest thing I found to doing the trick is this code,
string key = Console.ReadKey().ToString();
if (key == "")
{
Console.WriteLine("User pressed enter!");
return;
}
However, this doesn't do what I want it to. For this, if I press Enter it just takes to to the "press any button to close this app". If anyone could help that would be great.
Thanks.
In some cases it's enough to place Console.ReadLine() at the end of the Main method:
static void Main(string[] args) {
// your code here
Console.ReadLine();
}
Is your application a Console Application? Or is it a Windows Forms Application?
For a Console Application, which by default closes automatically at the conclusion of execution, we would need to prevent the application from closing until the user presses the Enter key. This can be done easily using the following code:
ConsoleKeyInfo keyInfo;
do { keyInfo = Console.ReadKey(true); }
while (keyInfo.Key != ConsoleKey.Enter);
For a Windows Forms Application, a different approach is required. We would need to intercept the Enter key when the user presses it and close the form, which will exit the application if it is the main form. We can accomplish via the KeyUp() event of the form:
private void MainForm_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
this.Close();
}
}
The event handler can be added from the designer, or from code using the following statement:
this.KeyUp += MainForm_KeyUp;
Finally, in order listen to key events regardless of what control on the form has focus, we need to set the KeyPreview property of the form to true, which can be done within the designer, or in code as follows:
public MainForm()
{
InitializeComponent();
// Set KeyPreview property to listen for key events:
this.KeyPreview = true;
}
I'm going to assume it is a console application.
This is the way I do it:
Use a 'while'-loop and break when wanting to stop
Explained with some code:
static void Main(string[] args)
{
while (true)
{
Console.WriteLine("test");
ConsoleKeyInfo key = Console.ReadKey();
if (key.Key == ConsoleKey.Enter) break;
else Console.WriteLine("You gave something else");
Console.WriteLine("This is the end of the app");
break;
}
}
Google is your friend. The answer is a simple modification to your if statement of ConsoleKey.Enter as seen here:
public static void Main()
{
DateTime dat = DateTime.Now;
Console.WriteLine("The time: {0:d} at {0:t}", dat);
TimeZoneInfo tz = TimeZoneInfo.Local;
Console.WriteLine("The time zone: {0}\n",
tz.IsDaylightSavingTime(dat) ?
tz.DaylightName : tz.StandardName);
Console.Write("Press <Enter> to exit... ");
while (Console.ReadKey().Key != ConsoleKey.Enter) {} // <-- check for enter key
}
Original information here
Related
the following scenario is given:
Welcome screen appears. If user has read the welcome text he has 2 choices:
a) pressing ENTER to continue an getting the next text
b) pressing the E-Key in oder to leave the program
So my problem is:
how can I check if the user pressed the ENTER-Key?
what i tried so far - just as very primitive prototype
...var userInput= Console.ReadLine();
if (userInput == "\r")
{
Console.WriteLine("correct");
}
else
{
Console.WriteLine("wrong");
}....
I also tried it via Regex but I didn't make it run. Thanks for helping...
Just like this (with Console.ReadKey):
static void Main(string[] args)
{
Console.WriteLine("Hello Mr.Sun! Try press enter now:");
var userInput = Console.ReadKey();
if(userInput.Key == ConsoleKey.Enter)
{
Console.WriteLine("You pressed enter!");
} else
{
Console.WriteLine("You pressed something else");
}
}
I'm very new to C# and have started to create a little text-based game in the console before I get into the more technical stuff. On my start menu, I was looking to make a simple flashy 'Press Enter to continue', which loops on and off until the user presses Enter.
while (!enter)
{
WhiteText();
Console.SetCursorPosition(47, 15);
Console.WriteLine("[Press 'Enter' to start game]");
System.Threading.Thread.Sleep(2000);
BlackText();
Console.SetCursorPosition(47, 15);
Console.WriteLine("[Press 'Enter' to start game]");
System.Threading.Thread.Sleep(1000);
}
Essentially I want that repeating while I check if the user has actually pressed enter. I used an if statement with ConsoleKeyInfo input = Console.ReadKey(); which then checks if they've pressed enter. My problem is that I can't seem to get both to run together. Is this something that's even possible in the console.
I'm really hoping I made this clear with my limited knowledge, any help or insight on this would be very appreciated.
You can use Console.KeyAvailable before reading the key.
But when the user presses enter the input will be processed only after the end of the Thread.Sleep . So it'll feel slow to the user
bool show = true;
while (true)
{
if (Console.KeyAvailable)
{
ConsoleKeyInfo key = Console.ReadKey(true);
if (key.Key == ConsoleKey.Enter)
break;
}
Console.ForegroundColor = show ? ConsoleColor.White : ConsoleColor.Black;
Console.SetCursorPosition(47, 15);
Console.WriteLine("[Press 'Enter' to start game]");
System.Threading.Thread.Sleep(show ? 2000 : 1000);
show = !show;
}
I want to make a little game. The program will output numbers in a loop, and the person has to stop the loop in the exact number that was specified before, by clicking the 'enter' key. like so:
static void Main(string[] args)
{
Console.WriteLine("try to click the 'enter' button when the program shows the number 4");
for (int i = 0; i < 10; i++)
{
Console.WriteLine(i);
//here will be the command which reads the enter key and stops the loop
}
}
One of the users told me to use this code:
Console.WriteLine("try to click the 'enter' button when the program shows the number 4");
for (int i = 0; i < 10; i++)
{
Console.WriteLine(i);
if (e.KeyChar == (char)13)
{
break;
}
}
The problem is, when i use this code, i have an error which says 'the name 'e' does not exist in the current context'.
What does that mean?
Thanks in advance.
There are two basic methods for reading console input:
Console.ReadLine() will pause and wait for the user to enter text followed by the enter key, returning everything entered before the enter key is pressed as a string.
Console.ReadKey() will wait for a keypress and return it as a ConsoleKeyInfo structure with information on the key pressed, what character (if any) it represents and what modifier keys (ctrl, alt, shift) were pressed.
If you don't want to wait until the user presses a key you can use the Console.KeyAvailable property to check if there is a keypress waiting to be read. This can be used in a timing loop to provide a timeout for key entry:
DateTime endTime = DateTime.Now.AddSeconds(10);
while (DateTime.Now < endTime)
{
if (Console.KeyAvailable)
{
var key = Console.ReadKey();
if (key.Key == ConsoleKey.Enter)
{
// do something with key
//...
// stop waiting
break;
}
}
// sleep to stop your program using all available CPU
Thread.Sleep(0);
}
I found a basic idea for a solution to your problem here.
In this answer he is using the Console.KeyAvaliable property to check if a Key has been pressed and then checks if the press key is the one you are lookig for.
To fit it to your needs you have to change it like so:
static void Main (string[] args)
{
Console.WriteLine ("try to click the 'enter' button when the program shows the number 4");
int counter = 0;
int limit = 100000;
do {
while (counter < limit && !Console.KeyAvailable) {
Console.WriteLine (counter);
counter++;
}
} while (Console.ReadKey (true).Key != ConsoleKey.Enter);
}
Try:
ConsoleKeyInfo cki;
do
{
cki = Console.ReadKey();
//What you need to do code
} while (cki.Key != ConsoleKey.Enter);
Console.ReadKey() will wait for a keypress and return it as a ConsoleKey, you just catch and test if it's your desired key.
This is my main function:
var configKey = Task.Factory.StartNew(acceptConfig);
var devKey = Task.Factory.StartNew(acceptDevMode);
while (true)
{
doSomething();
if (configKey.IsCompleted)
{
getFirstChoice();
getSecondChoice();
getThirdChoice();
configKey = Task.Factory.StartNew(acceptConfig);
}
if (devKey.IsCompleted)
{
setDevPassword();
getFirstChoice();
getSecondChoice();
getThirdChoice();
devKey = Task.Factory.StartNew(acceptDevMode);
}
}
And these are my functions:
private static void acceptConfig()
{
var key = Console.ReadKey(true);
while (key.Key != ConsoleKey.C)
{
key = Console.ReadKey(true);
}
}
private static void acceptDevMode()
{
var key = Console.ReadKey(true);
while (key.Key != ConsoleKey.D)
{
key = Console.ReadKey(true);
}
}
These are basically my getChoice functions:
var key = Console.ReadKey(true);
switch (key.Key)
{
case ConsoleKey.D1
...
And this is my setDevPassword() function:
private static void setDevPassword()
{
password = Convert.ToInt32(Console.ReadLine());
}
My problem is that except for the first time either C or D is pressed, every other time the user has to press the key twice for the program to respond. In every getChoice function, the user needs to press the digit twice, and when coming back to the main while loop again, clicking C or D won't do anything on the first press - only on the second one.
Same goes for the setDevPassword() function, except there the user has to press the keys twice before the programs responses for the next key press. That means it's one more key press (that doesn't do anything) than in the other input functions.
I'm not sure if those Tasks and the IsCompleted checks are really good practice in my case, but are they the reason the user input is so "laggy"? Why is this happening?
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
how to handle key press event in console application
a simple question.
I am writing a simple text based adventure game for fun and I am stuck on the first part already! How can I make my console check for key presses I.E: press enter to continue!
You can use
Console.ReadKey();
To read 1 key. You could then do something like this:
string key = Console.ReadKey().Key.ToString();
if(key.ToUpper() == "W")
Console.WriteLine("User typed 'W'!");
else
Console.WriteLine("User did not type 'W'");
Or:
if(key == "")
Console.WriteLine("User pressed enter!");
else
Console.WriteLine("User did not press enter.");
And if you do not care if the user types anything but presses enter after, you could just do:
// Some code here
Console.ReadLine();
// Code here will be run after they press enter
The Console class contains all the methods needed to read and write to the 'console'
For example
Console.Write("Press Enter to continue!")
do
{
ConsoleKeyInfo c = Console.ReadKey();
} while (c.Key != ConsoleKey.Enter);
Console.Write("Press Enter to continue!")
Console.ReadLine();
The program will not continue until the user hits Enter.
You can also check for other specific keys using Console.ReadKey:
void WaitForKey(ConsoleKey key)
{
while (Console.ReadKey(true).Key != key)
{ }
}
Usage:
Console.Write("Press 'Y' to continue.");
WaitForKey(ConsoleKey.Y);
An event, that would do it.
private void OnKeyDownHandler(object sender, KeyEventArgs e)
{
if (e.Key == Key.Return)
{
Console.Write("Press Enter to continue!")
}
}