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How to be dynamically either console application or Windows Application
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Closed 4 years ago.
I have this task given to me and have no idea how to approach it.. Everywhere online says that this isn't possible without .dll or mocking.
The server, when launched with an argument of –w should open a windowed interface that
permits an operator to control the functions of the server. If launched with no arguments it
should operate as previously specified in part 1
(part 1 is a console application)
I don't know if I'm missing something obvious.
Thanks for any help you can give
I don't know where you're seeing on-line that this isn't possible. Every Windows Forms application has a Main method, you just need to modify it a bit.
[STAThread]
static void Main(string[] args)
{
if (args.Length > 0)
{
File.WriteAllText("hello.txt", "foo");
}
else
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Form1());
}
}
I added the string[] args argument and then check it. I'm not checking for -w, I'm just checking for any old argument, but you should be able to take it from there.
It's absolutely not impossible. Just add reference to System.Windows.Forms, add it in the using clause, and go from here.
using System;
using System.Collections.Generic;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Linq;
namespace ConsoleWindow
{
class Program
{
static void Main(string[] args)
{
if (args.Contains("-w"))
{
Form1 f1 = new Form1();
f1.ShowDialog();
}
Console.ReadKey();
}
}
}
Related
I just created my first .NET 6 console app, and instead of the default,
using System;
using System.Collections.Generic;
using System.Linq;
namespace MyApp
{
public class Program
{
public static void Main(string[] args)
{
Console.WriteLine("Hello World!");
}
}
}
I got:
// See https://aka.ms/new-console-template for more information
Console.WriteLine("Hello, World!");
And even when there's no class, the program runs! I took a look at the link provided in the comments, but I don't know if this is a new feature or an old one. If this is a new feature, does that mean C# will be allowing C-style programming hereafter?
It's a new feature of C# 9 or 10. Microsoft documentation says following:
Top-level statements enable you to avoid the extra ceremony required by placing your program's entry point in a static method in a class. The typical starting point for a new console application looks like the following code:
using System;
namespace Application
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Hello World!");
}
}
}
The preceding code is the result of running the dotnet new console command and creating a new console application. Those 11 lines contain only one line of executable code. You can simplify that program with the new top-level statements feature. That enables you to remove all but two of the lines in this program:
Console.WriteLine("Hello, World!");
I made an application in C#, where I open a virtual keyboard. I also have a Lua application that runs this keyboard, and both are functional. In this scenario I needed to send some information from Lua to C# by the command line, but I'm not having success, does anyone know if it is possible, and if so, how could I do it?
Code Lua-
os.execute('C:\Users\Public\Documents\Keyboard.exe')
The code just calls the executable.
Code C#-
namespace WindowsFormsApp2
{
static class Program
{
[STAThread]
static void Main(string[] args)
{
// Test if input arguments were supplied.
if (args.Length >= 0)
{
Console.ReadLine();
}
Console.WriteLine(args.Length);
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Keyboard());
}
}
}
Here I read the console, but I'm not sending any code through Lua to read through C#, in this case I wanted to send a parameter through lua, and receive it through C#, but I don't know how to implement this through Lua.
I am trying to just get information from the clipboard in a simple bit of code. I have done lots of searching but none of the posts have solved my issue. I have ensured that I am using System.Windows.Forms;
below is the code. Am I missing something else?
//Rextester.Program.Main is the entry point for your code. Don't change it.
//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;
using System.Windows.Forms;
namespace Rextester
{
public class Program
{
public static void Main(string[] args)
{
Clipboard.SetText(txtCopy.Text);
txtPaste.Text = Clipboard.GetText();
}
}
}
Below are the errors when I run the code
Error(s):
(22:13) The name 'Clipboard' does not exist in the current context
(22:31) The name 'txtCopy' does not exist in the current context
(23:13) The name 'txtPaste' does not exist in the current context
(23:29) The name 'Clipboard' does not exist in the current context
You have change the Program.main() method of windows Form application, and you are not launching any Form from it. There should be something like this inside that method.
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Form1());
This is the method that is call when you run the program, and is not initializing any Form.
You need to reference System.Windows.Forms at the start of your file in order to resolve the Clipboard missing error. The MSDN page for it is here if you want to look.
You also never define your txtCopy and txtPaste variables so these are showing as missing references too.
I'm assuming txtCopy and txtPaste are some kind of input within a form? If this is the cast you're not initialising your form as you never create one, so nothing will be generated. That being said even if you add the initialisation you won't be able to access the controls from within the main method as the objects will be out of scope as they're contained in the Form class itself.
Assuming you are using a VS basic template you should structure your code as follows to achieve your functionality.
Program.cs:
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Form1());
}
Form1.cs
public Form1()
{
InitializeComponent();
/* Once you call the InitializeComnents method you will be able to access controls added in design view */
Clipboard.SetText(txtCopy.Text);
txtPaste.Text = Clipboard.GetText();
}
Remember your using statements too!
Is it possible to run a windows form application with the console application?
And if so, how would i use the Main() void?
And how could i pass strings over from the windows form to the console?
I think that what you are saying is that you want to have a console application that can simply open a form. You can do this.
Create your console application as per normal but then add your form to your project (or a reference to a project that contains the form). Then you just want something like this.
using System;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("I'm going to open a form now!");
var form = new Form1();
form.ShowDialog();
}
}
}
If you want to add information to your form, you could add properties to the form or a add a custom constructor which takes string information you want sent to the form.
First Create the windows Application like normally you do.
Create a new Console Application
In solution Explorer, goto References->Add Reference->Click Browse Tab->Select Project Path to Debug->Select the Application
Also add a Reference to System.Windows.Form;
In the code
Include the namespace of the Application
using NewForm;// Example
class Program
{
static void Main(string[] args)
{
TestForm t = new TestForm(); //Class of WindowsFormApplication NewForm
t.ShowDialog();
}
}
}
I am trying to prevent my program from running multiple instances at any given time. I have read about using mutex and windows events, however both threads were several years old, and I'm curious if with .net4 there is a more simple, and more elegant way to deal with this? I thought I had read about a setting for the form that allowed you to deny multiple instances by the property? Could someone shed some light on what the safest and/or simplest way to prevent multiple instances of a program is?
The safest way is to use the built-in support in .NET, WindowsFormsApplicationBase.IsSingleInstance property. Hard to guess if it is appropriate, you didn't make much effort describing your exact needs. And no, nothing changed in the past 5 years. – Hans Passant Jan 7 at 0:38
This was the best answer but Hans didn't submit it as an answer.
In VB you can set this at the project level (Properties > General) for Winforms projects.
In C# you can use code similar to this.. needs conversion of course..
Dim tGrantedMutexOwnership As Boolean = False
Dim tSingleInstanceMutex As Mutex = New Mutex(True, "MUTEX NAME HERE", tGrantedMutexOwnership)
If Not tGrantedMutexOwnership Then
'
' Application is already running, so shut down this instance
'
Else
'
' No other instances are running
'
End If
Whoops, I forgot to mention that you will need to place GC.KeepAlive(tSingleInstanceMutex) after your Application.Run() call
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Windows.Forms;
namespace YourNameSpaceGoesHere
{
static class Program
{
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
if (Process.GetProcessesByName("YourFriendlyProcessNameGoesHere").Length > 1)
{
MessageBox.Show(Application.ProductName + " already running!");
Application.ExitThread();
}
else
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new YourStartUpObjectFormNameGoesHere());
}
}
}
}