Develop Reference

Passing Command Line Arguments from VB to C# WPF Application

I have a C# WPF application which I want to be able to open from another existing application, which was written in VB.net. As far as the c# application goes, I think I know how to get command line parameters that are passed to it two different ways, which I got while researching google and using others' answers.
App.xaml Header
<Application x:Class="ChallengeHandler.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:ChallengeHandler"
Startup="Application_Startup">
App.xaml.cs Method 1
private void Application_Startup(object sender, StartupEventArgs e)
{
string[] args = Environment.GetCommandLineArgs();
if (args.Length < 1)
{
MessageBox.Show("No parameter provided. Failed to run.");
Shutdown();
}
else
{
MainWindow wnd = new MainWindow(args[0]);
wnd.Show();
}
}
The above method will result in the application opening but none of the data, which relies on the parameter, is populated. So the comboboxes and stuff in the views are just empty. That fails.
App.xaml.cs Method 2
private void Application_Startup(object sender, StartupEventArgs e)
{
if (e.Args.Length < 1)
{
MessageBox.Show("No parameter provided. Failed to run.");
Shutdown();
}
else
{
MainWindow wnd = new MainWindow(e.Args[0]);
wnd.Show();
}
}
This method just shows the error messagebox each time, as the args is empty.
I have a feeling the issue is when I'm trying to open the application from the VB.NET application and pass the string parameter to the c# app from there. But I am out of ideas on how to pass a string like a command line parameter from the VB.net code.
Calling from a VB.net Application
Dim sPath As String = Environment.GetFolderPath(Environment.SpecialFolder.Programs) + "\Microsoft\ChallengeHandler.appref-ms"
Dim pHelp As New ProcessStartInfo
If System.IO.File.Exists(sPath) Then
pHelp.FileName = sPath
pHelp.Arguments = "097"
pHelp.UseShellExecute = True
pHelp.WindowStyle = ProcessWindowStyle.Normal
Dim proc As Process = Process.Start(pHelp)
End If
I have tried the VB code without the
pHelp.UseShellExecute = True
pHelp.WindowStyle = ProcessWindowStyle.Normal
with no avail; I added them in the hope the shell execute would force the parameters as command line parameters. I have also tried this in VB:
2nd VB Method
Dim sPath As String = Environment.GetFolderPath(Environment.SpecialFolder.Programs) + "\Microsoft\ChallengeHandler.appref-ms"
If System.IO.File.Exists(sPath) Then
System.Diagnostics.Process.Start(sPath, "097")
End If
Any insight would be GREATLY appreciated! Thanks.

I see you're using "\Microsoft\ChallengeHandler.appref-ms". This is a ClickOnce application. Getting the parameters for a ClickOnce application is completely different from a normal application. You need to use ApplicationDeployment.CurrentDeployment.ActivationUri.Query and HttpUtility.ParseQueryString for retrieving them.
I believe to send them across you'll have to add them to the launch url by using "?param=value". I've only tried launching it from a web page, so I'm unsure if this is how it works.
The method you're currently using is valid for normal application. If you can locate the exe and launch that directly, you should be fine.

I created 2 projects: Line command C# invoker and a WPF Test application;
The invoker code on Program.cs:
namespace WPFInvoker
{
class Program
{
static void Main(string[] args)
{
Process.Start(#"C:\Users\...\bin\Debug\WPF_Test.exe", "example_parameter");
}
}
}
Then on the WPF App.xaml I have the startup event app_Startup and the main form MainWindow.xaml:
<Application x:Class="WPF_Test.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:WPF_Test"
Startup="app_Startup"
StartupUri="MainWindow.xaml">
<Application.Resources>
</Application.Resources>
</Application>
And the App.xaml.cs code is:
namespace WPF_Test
{
/// <summary>
/// Interaction logic for App.xaml
/// </summary>
public partial class App : Application
{
void app_Startup(object sender, StartupEventArgs e)
{
if (e.Args != null && e.Args.Length > 0)
{
MessageBox.Show(e.Args[0]);
}
else
{
MessageBox.Show("e.Args is null");
}
}
}
}
When I open the WPFTest.exe with a double click shows a MessageBox with the message "e.Args is null":
Application without parameters
But if I open the WPFTest application through WPFInvoker:
Application with parameter
Finally I close the MessageBox and the MainWindow.xaml its shown.

Nothing happening when you click second time

I having terrible when i execute the same method second time.i am not getting WPF screen, I don't know why?
refer my code
TestWindow Button click method(it is windows application project type) and i have removed STA thread in my
Main()
TestClass test;
private void button1_Click(object sender, EventArgs e)
{
test =TestClass.Instance; //singleton pattern
test.ShowScreen();
}
TestClass
public void ShowScreen()
{
var thread = new Thread(() =>
{
Explorer explorer = new Explorer();
explorer.Show();
explorer.Closed += (s, args) =>
explorer.Dispatcher.InvokeShutdown();
System.Windows.Threading.Dispatcher.Run();
});
thread.SetApartmentState(ApartmentState.STA);
thread.Start();
}
Above the code working fine when i run 1st time. i can able view my explorer screen.
But the problem is when i close 1st screen and call once again the same method(test.ShowScreen();) the explorer screen not showing
Note : I have noticed If i didn't close the 1st window(instance) then i can able open many explorer screen. using the same code. If i closed the 1st window(instance) and i am unable open explorer screen and i am not getting any error message.

The issue is resolved Adding the following line in the TestClass Constructors
using SW = System.Windows;
private TestClass()
{
if (SW.Application.Current == null)
{
new SW.Application
{
ShutdownMode = SW.ShutdownMode.OnExplicitShutdown
};
}
}

Directx device doesn't initialize for window, Program hang

I've tried following several tutorials an have seem to be having trouble.
I've got an existing program that i'm trying to add a directx window to as an additional popup forum that will run as a child to the main application form.
Here is the windows form class:
public partial class DxWindow : Form
{
Device device;
public DxWindow()
{
InitializeComponent();
initDevice();
}
private void initDevice()
{
MessageBox.Show("hello");
PresentParameters pp = new PresentParameters();
pp.Windowed = true;
pp.SwapEffect = SwapEffect.Discard;
device = new Device(0, DeviceType.Hardware, this, CreateFlags.HardwareVertexProcessing, pp);
}
private void Render()
{
//render stuff
}
private void DxWindow_Paint(object sender, PaintEventArgs e)
{
Render();
}
}
and here is where i initialize the form (from a UI button in main window)
private void toolStripButton3_Click_1(object sender, EventArgs e)
{
if (DirectxWindow == null)
{
DirectxWindow = new DxWindow();
DirectxWindow.Show();
}
}
When i run the program and click the button. it seems create the form in memory but never shows up. when i step through it in the debugger, it gets to "DirectxWindow = new DxWindow();" and then automatically jumps out of break mode and continues running with the main window frozen and no new Dxwindow().
when i break execution is seems to still be on "DirectxWindow = new DxWindow();"
Also, "MessageBox.Show("hello");" in the DxWindow constructor is never called"
Edit: I've deduced that as soon as it hits "PresentParameters pp = new Microsoft.DirectX.Direct3D.PresentParameters();" the application becomes unresponsive without throwing any errors.

Turns out my problem was needing to use
<startup useLegacyV2RuntimeActivationPolicy="true">
in the "App.config" File
Solution was found here: Mixed mode assembly is built against version 'v1.1.4322'
Although i never got the error as described by the OP. i simply had this problem as described in the comments:
"Thank you!!!! This is the weirdest problem I'd ever encountered. In VS 2012 .Net 4.0 my application would just hang the moment I initialized any variable of a type related to this DLL. I'd never seen anything like it. Couldn't find anything about the problem until I found this!" – Quinxy von Besiex

WPF Application exit code

I am trying to set and get the application exit code .
I am trying to do something following :
protected override void OnStartup(StartupEventArgs e)
{
base.OnStartup(e);
if ( e.Args.Length != 0)
{
}
else
{
new MainWindow().ShowDialog();
}
Environment.ExitCode = 110;
this.Shutdown();
}
And then I am trying in cmd to get it by echo %ERRORLEVEL%
But I get always result 0 , any idea what is the issue ?

For WPF, try
Application.Current.Shutdown(110);
Note that the application needs to be running as a console app. This answer is the easiest way I know of; the accepted answer looks more difficult.
An easy test to tell if you're running in console mode: call your app from the command line (make sure your code doesn't shut down right away). The main window should be showing. If you can type another command in the console, your app is not running in its context. The command prompt should be locked, waiting for you to close the window.

You can do it in Main method. Just change its return-value-type to int instead of void and return your exit-code
static int Main(string[] args) {
// something to do
Console.ReadKey();
return 110;
}
UPDATE:
To create a custom Main in WPF application, you should follow these steps:
First: unload the project by right-click on it in Solution Explorer
and click on Unload Project
Modify the .csproj file by change the <ApplicationDefinition Include="App.xaml"> to this one: <Page Include="App.xaml">
Now you can create your own Main method in your project:
Sample Main method and App class:
public partial class App : Application {
[STAThread]
public static int Main() {
App app = new App();
app.InitializeComponent();
var i = app.Run();
return i;
}
public App() : base() { }
protected override void OnExit(ExitEventArgs e) {
e.ApplicationExitCode = 110;
base.OnExit(e);
}
}

override the OnExit method, and in the ExitEventArgs you can set that value.
protected override void OnExit(ExitEventArgs e)
{
e.ApplicationExitCode = your_value;
}

It works for me with either method (Environment.ExitCode=110 or Environment.Exit(110)). I hope you are calling the program from the console and not from Visual Studio to then check the ExitCode...

Do it like this:
Environment.Exit(110);
This will terminate the current application with exit code 110.

You can do this in the following ways...
Application.Current.Shutdown(110);
Environment.Exit(10);
this.Close();
Shoutdown() returns a code. and Exit() also returns an exit code, but Close() only closes the application.

Delaying Window for Splash Screen

I am developing a project and I want to add to it a splash screen. I have checked questions here on Stackoverflow and other blogs and MSDN etc. but could not find the solution I am looking for.
I want my SplashScreen,
1- appear and stay on the screen 3-4 seconds but at the same time I want my Main Window NOT TO appear. When my splash screen fades out completely then Main Window should appear. Many of the examples I have checked out do not implement this. Even though I set SplashScreen.Close.(TimeSpan.FromMiliseconds(4000)) MainWindow still apeear immediately front or back of SplashScreen. They say "add an image to your project, make it's Build Action SplashScreen or Resource, if you want to handle fade out time go App.xaml.cs file and implement your own Main() method and put your logic." I know that already. It does not work.
2- If possible I want my splashscreen NOT TO fade out slowly. I want it to disappear suddenly.(if this is not possible or really hard for a intermediate developer to do it, it is ok. you may disregard.)
And please I want C# code not Xaml. My project is based on WPF adn .NET 4.0 client profile.
Thank you.

Why don't you make your splash screen a fully qualified XAML <window> and in your App.xaml set it up as your StartupUri:
<Application x:Class="MyApp.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
StartupUri="SplashWindow.xaml">
Then in your splash window's Load Event you initialize the main window (preferably somewhere else so the instance sticks around when you close the splash). From here you can also specify a timer for x-seconds to go off and show the main window / hide the splash window.
using System.Threading;
/// -------------------------------
private Timer t;
private void Window_Loaded(object sender, RoutedEventArgs e)
{
App.MainWindow = new MainWindow(); // Creates but wont show
t = new Timer(new TimerCallback(CloseSplash), null, new TimeSpan(0,0,10), new TimeSpan(0,0,0,0,-1));
// Do Other load stuff here?
}
private void CloseSplash(object info)
{
// Dispatch to UI Thread
Dispatcher.Invoke(DispatcherPriority.Normal, x => CloseSplashMain());
}
private void CloseSplashMain()
{
App.MainWindow.Show()
this.Close();
}
You'll have to change your app's main window behaviour though, otherwise closing the splash window will cause the app to close.
public partial class App : Application
{
private void Application_Startup(object sender, StartupEventArgs e)
{
App.Current.ShutdownMode = ShutdownMode.OnLastWindowClose;
}
}
Also don't forget to dispose your timer when you're done. It's an IDisposable and will keep firing that method unless it's stopped.

There are answers but I find a an easier one. Just use the Thread.Sleep(int miliSeconds) method in the main window's constructor. This will delay your app in order to open specified miliseconds later.

In the constructor of App.xaml.cs open your splash screen, wait for a few seconds, then close before proceeding with rest of the app. I am using Unity, so I close the splash screen somewhere after the Boostrapper has initialized some services.
public partial class App : Application
{
private static SplashScreen _splashScreen;
public App()
{
OpenSplashScreen();
new Bootstrapper().Run();
}
private void OpenSplashScreen()
{
_splashScreen = new SplashScreen("SplashScreen/splash.jpg");
_splashScreen.Show(false);
}
internal static void CloseSplashScreen(double time)
{
_splashScreen.Close(TimeSpan.FromSeconds(0));
_splashScreen = null;
}
}
where Bootstrapper.cs is listed below:
public class Bootstrapper : UnityBootstrapper
{
protected override void ConfigureContainer()
{
base.ConfigureContainer();
var section = (UnityConfigurationSection)ConfigurationManager.GetSection("unity");
section.Configure(Container);
// initialize some services before
App.CloseSplashScreen(0);
}
protected override IModuleEnumerator GetModuleEnumerator()
{
return new ExtendedConfigurationModuleEnumerator();
}
protected override DependencyObject CreateShell()
{
MainWindow shell = new MainWindow(Container);
shell.Show();
return shell;
}
}

The best way and using the API is
SplashScreen splash = new SplashScreen("splashscreen.jpg");
splash.Show(false);
splash.Close(TimeSpan.FromMilliseconds(2));
InitializeComponent();