[c#] Why is the console window closing immediately once displayed my output?

the issue here is that their Hello World Program is showing up then it would immediately close.
why is that?

Because it's finished. When console applications have completed executing and return from their main method, the associated console window automatically closes. This is expected behavior.

If you want to keep it open for debugging purposes, you'll need to instruct the computer to wait for a key press before ending the app and closing the window.

The Console.ReadLine method is one way of doing that. Adding this line to the end of your code (just before the return statement) will cause the application to wait for you to press a key before exiting.

Alternatively, you could start the application without the debugger attached by pressing Ctrl+F5 from within the Visual Studio environment, but this has the obvious disadvantage of preventing you from using the debugging features, which you probably want at your disposal when writing an application.

The best compromise is probably to call the Console.ReadLine method only when debugging the application by wrapping it in a preprocessor directive. Something like:

#if DEBUG
    Console.WriteLine("Press enter to close...");
    Console.ReadLine();
#endif

You might also want the window to stay open if an uncaught exception was thrown. To do that you can put the Console.ReadLine(); in a finally block:

#if DEBUG
    try
    {
        //...
    }
    finally
    {
        Console.WriteLine("Press enter to close...");
        Console.ReadLine();
    }
#endif

Examples related to c#

How can I convert this one line of ActionScript to C#? Microsoft Advertising SDK doesn't deliverer ads How to use a global array in C#? How to correctly write async method? C# - insert values from file into two arrays Uploading into folder in FTP? Are these methods thread safe? dotnet ef not found in .NET Core 3 HTTP Error 500.30 - ANCM In-Process Start Failure Best way to "push" into C# array

Examples related to .net

You must add a reference to assembly 'netstandard, Version=2.0.0.0 How to use Bootstrap 4 in ASP.NET Core No authenticationScheme was specified, and there was no DefaultChallengeScheme found with default authentification and custom authorization .net Core 2.0 - Package was restored using .NetFramework 4.6.1 instead of target framework .netCore 2.0. The package may not be fully compatible Update .NET web service to use TLS 1.2 EF Core add-migration Build Failed What is the difference between .NET Core and .NET Standard Class Library project types? Visual Studio 2017 - Could not load file or assembly 'System.Runtime, Version=4.1.0.0' or one of its dependencies Nuget connection attempt failed "Unable to load the service index for source" Token based authentication in Web API without any user interface

Examples related to console-application

How to run .NET Core console app from the command line ASP.NET Core configuration for .NET Core console application How to keep console window open How to navigate a few folders up? How to stop C# console applications from closing automatically? Could not load file or assembly ... An attempt was made to load a program with an incorrect format (System.BadImageFormatException) Can I write into the console in a unit test? If yes, why doesn't the console window open? What is the command to exit a Console application in C#? Can't specify the 'async' modifier on the 'Main' method of a console app Why is the console window closing immediately once displayed my output?

Examples related to msdn

Why is the console window closing immediately once displayed my output?