在C＃中经过X秒钟后使cmd吗？

Question

I'm trying to make the console window close after an X amount of seconds here's an example:

My program says "Type in a number:"

Then I type "1945"

After I type the number the console says "Unlocked".

The problem is that I want the console to re-run the original message after 3-4 seconds so that it just continuously will do this in a loop.

Down below I have included the current code with comments on where I want it do do my wanted things.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace portkod
{
class Program
{
    static void Main(string[] args)
    {
        Console.WriteLine("Kod:");

        int kod = Convert.ToInt32(Console.ReadLine());
        DateTime tiden = DateTime.Now;



        if (kod == 1946)
        {
            Console.Clear();

            //After this message comes up I want the program to ask for "Kod:"
            //again after like 3-4 seconds.

            Console.WriteLine("Unlocked!");
        }
        else if (kod != 1946)
        {
            Console.Clear();

            Console.WriteLine("Locked!");
        }
        Console.ReadLine();
    }
}
}

Answer 1

You could do it like this.

The GetIntFromConsole reads from the console, and only returns a nr when a valid integer was given, if not asks at once again.

As long as the user doesn't give in 1946, the program repeats the question after 4 seconds, and marks 'Locked'

using System;
using System.Threading;

namespace Repeat
{
    class Program
    {
        static int GetIntFromConsole(string label)
        {
            int result;
            string input;
            do
            {
                Console.Write("{0}: ", label);
                input = Console.ReadLine();
            } while (!int.TryParse(input, out result));
            return result;
        }

        static void Main(string[] args)
        {
            int result;
            result = GetIntFromConsole("Kod");
            while (result != 1946)
            {
                Console.WriteLine("Locked");
                Thread.Sleep(4000); // 4 seconds = 4000 milliseconds
                result = GetIntFromConsole("Kod");
            } 
            Console.WriteLine("Unlocked");
        }
    }
}

As requested, i will try to explain a bit more

the GetIntFromConsole can be called from anywhere inside the program, and will return only a valid parsed integer, that means empty strings, or anything else than numbers will not parse correctly, and the user will have to retry

The loop used here, is the do { this logic } while (condition is met)

This means, when you are using a do / while loop you will always enter this loop, until the condition after while returns false

The while loop inside the Main, checks a condition first, and if this one is true, it goes into the loop, if not it skips forward to Console.WriteLine("Unlocked").

in case you want to run a continuous loop as mentioned in your comments below, you can to it in the following way:

static void Main(string[] args)
{
    int result;
    while (true)  // always true, it will always repeat
    {
        result = GetIntFromConsole("Kod");
        while (result != 1946)
        {
            Console.WriteLine("Locked");
            Thread.Sleep(4000); // 4 seconds = 4000 milliseconds
            result = GetIntFromConsole("Kod");
        } 
        Console.WriteLine("Unlocked");
        Thread.Sleep(4000);
    }
}

this new while loop will loop until you issue a break; statement, since it restarts the logic again from on: result = GetIntFromConsole("Kod"); your result will be re-evaluated and you can lock / unlock the screen again a few times ;)

I hope that was a sufficient explanation, i'm not very much of a teacher :)

Answer 2

You can use Thread.Sleep to wait some time.

static void Main(string[] args)
{
    while (getKod() != 1946)
    {

        System.Threading.Thread.Sleep(3000);
    }
    Console.WriteLine("Unlocked");
}


static int getKod()
{
    Console.WriteLine("Kod:");
    int kod;
    Int32.TryParse(Console.ReadLine(), out kod);
    return kod;
}