Csharp/C Sharp/Development Class/Application Event

Application.Run

 


using System.Windows.Forms;
   
class RunFormBetter
{
     public static void Main()
     {
          Form form = new Form();
   
          form.Text = "My Very Own Form";
   
          Application.Run(form);
     }
}

Handling Application Events: On Application Exit

using System;
using System.Threading;
using System.Reflection;
using System.Windows.Forms;
   
public class HelloWorldForm : Form
{
    public HelloWorldForm()
    {
        Text = "Hello, WindowsForms!";
    }
}
   
public class ApplicationEventHandlerClass
{
    public void OnApplicationExit(object sender, EventArgs e)
    {
        try
        {
            Console.WriteLine("The application is shutting down.");
        }
        catch(NotSupportedException)
        {
        }
    }
}
   
public class MainClass
{
    public static void Main()
    {
        HelloWorldForm FormObject = new HelloWorldForm();
        ApplicationEventHandlerClass AppEvents = new ApplicationEventHandlerClass();
   
        Application.ApplicationExit += new EventHandler(AppEvents.OnApplicationExit);
        Application.Run(FormObject);
    }
}

Handling Application Events: On Idle

using System;
using System.Threading;
using System.Reflection;
using System.Windows.Forms;
   
public class HelloWorldForm : Form
{
    public HelloWorldForm()
    {
        Text = "Hello, WindowsForms!";
    }
}
   
public class ApplicationEventHandlerClass
{
    public void OnIdle(object sender, EventArgs e)
    {
        Console.WriteLine("The application is idle.");
    }
}
   
public class MainClass
{
    public static void Main()
    {
        HelloWorldForm FormObject = new HelloWorldForm();
        ApplicationEventHandlerClass AppEvents = new ApplicationEventHandlerClass();
   
        Application.Idle += new EventHandler(AppEvents.OnIdle);
        Application.Run(FormObject);
    }
}

Handling Application Events: OnIdle, OnThreadException, OnThreadExit

 

using System;
using System.Threading;
using System.Reflection;
using System.Windows.Forms;
public class HelloWorldForm : Form {
    public HelloWorldForm() {
    }
    public static void OnApplicationExit(object sender, EventArgs e) {
        try {
            Console.WriteLine("shutting down.");
        } catch (NotSupportedException) {
        }
    }
    public static void OnIdle(object sender, EventArgs e) {
        Console.WriteLine("idle.");
    }
    public static void OnThreadException(object sender, ThreadExceptionEventArgs e) {
        Console.WriteLine("caught!");
    }
    public static void OnThreadExit(object sender, EventArgs e) {
        Console.WriteLine("thread is shutting down.");
    }
    public static void Main() {
        HelloWorldForm FormObject = new HelloWorldForm();
        Application.ApplicationExit += new EventHandler(OnApplicationExit);
        Application.Idle += new EventHandler(OnIdle);
        Application.ThreadException += new ThreadExceptionEventHandler(OnThreadException);
        Application.ThreadExit += new EventHandler(OnThreadExit);
        Application.Run(FormObject);
    }
}

Handling Application Events: On Thread Exit

using System;
using System.Threading;
using System.Reflection;
using System.Windows.Forms;
   
public class HelloWorldForm : Form
{
    public HelloWorldForm()
    {
        Text = "Hello, WindowsForms!";
    }
}
   
public class ApplicationEventHandlerClass
{
   
    public void OnThreadExit(object sender, EventArgs e)
    {
        Console.WriteLine("The application"s main thread is shutting down.");
    }
}
   
public class MainClass
{
    public static void Main()
    {
        HelloWorldForm FormObject = new HelloWorldForm();
        ApplicationEventHandlerClass AppEvents = new ApplicationEventHandlerClass();
   
        Application.ThreadExit += new EventHandler(AppEvents.OnThreadExit);
        Application.Run(FormObject);
    }
}

Handling Application Events: Thread Exception

using System;
using System.Threading;
using System.Reflection;
using System.Windows.Forms;
   
public class HelloWorldForm : Form
{
    public HelloWorldForm()
    {
        Text = "Hello, WindowsForms!";
    }
}
   
public class ApplicationEventHandlerClass
{
   
    public void OnThreadException(object sender, ThreadExceptionEventArgs e)
    {
        Console.WriteLine("an exception thrown from an application thread was caught!");
    }
}
   
public class MainClass
{
    public static void Main()
    {
        HelloWorldForm FormObject = new HelloWorldForm();
        ApplicationEventHandlerClass AppEvents = new ApplicationEventHandlerClass();
   
        Application.ThreadException += new ThreadExceptionEventHandler(AppEvents.OnThreadException);
        Application.Run(FormObject);
    }
}

Installing a Message Filter

 

using System;
using System.Windows.Forms;
   
public class BlockLeftMouseButtonMessageFilter : IMessageFilter
{
    const int WM_LBUTTONDOWN = 0x201;
    const int WM_LBUTTONUP = 0x202;
    
    public bool PreFilterMessage(ref Message m)
    {
        if(m.Msg == WM_LBUTTONDOWN)
        {
            Console.WriteLine("The left mouse button is down.");
            return true;
        }
        if(m.Msg == WM_LBUTTONUP)
        {
            Console.WriteLine("The left mouse button is up.");
            return true;
        }
        return false;
    }
}
   
public class MainForm : Form
{
    public static void Main()
    {
        MainForm MyForm = new MainForm();
        BlockLeftMouseButtonMessageFilter MsgFilter = new BlockLeftMouseButtonMessageFilter();
   
        Application.AddMessageFilter(MsgFilter);
        Application.Run(MyForm);
    }
   
    public MainForm()
    {
        Text = "Message Filter Test";
    }
}

Removing an Installed Message Filter

 

using System;
using System.Windows.Forms;
   
public class BlockLeftMouseButtonMessageFilter : IMessageFilter
{
    const int WM_LBUTTONDOWN = 0x201;
    
    public bool PreFilterMessage(ref Message m){
        if(m.Msg == WM_LBUTTONDOWN)
        {
            Console.WriteLine("The left mouse button is down.");
            Application.RemoveMessageFilter(this);
            return true;
        }
        return false;
    }
}
   
public class MainForm : Form
{
    public static void Main()
    {
        MainForm MyForm = new MainForm();
        BlockLeftMouseButtonMessageFilter MsgFilter = new BlockLeftMouseButtonMessageFilter();
        Application.AddMessageFilter(MsgFilter);
        Application.Run(MyForm);
    }
   
    public MainForm()
    {
        Text = "Message Filter Removal Test";
    }
}