ThreadExceptionEventArgs Class

Definition

Namespace:

System.Threading

Assemblies:

netstandard.dll, System.Threading.Thread.dll

Source:

ThreadExceptionEventArgs.cs

Provides data for the ThreadException event.

C#

public class ThreadExceptionEventArgs : EventArgs

Inheritance

Object

EventArgs

ThreadExceptionEventArgs

Derived

Microsoft.VisualBasic.ApplicationServices.UnhandledExceptionEventArgs

Examples

The following example allows you to raise a ThreadException event by clicking button1 on a form. The example creates two classes. The ErrorHandler class creates the form and the button that raises the event. The CustomExceptionHandler class provides the methods to handle the exception.

In Main in the ErrorHandler class, the code creates a new instance of the exception handling class, that is, an instance of the CustomExceptionHandler. Then the instance is added to the event, and the application is run.

In the OnThreadException method in the CustomExceptionHandler class, the example uses a try...catch...finally statement to process the exception. The ShowThreadExceptionDialog method creates the message to display, and displays it in a message box.

C#

using System;
using System.Threading;
using System.Windows.Forms;

// Create a form with a button that, when clicked, throws an exception.
 public class ErrorForm : System.Windows.Forms.Form
 {
    internal Button button1;

    public ErrorForm() : base()
    {
       // Add the button to the form.
       this.button1 = new System.Windows.Forms.Button();
       this.SuspendLayout();
       this.button1.Location = new System.Drawing.Point(100, 43);
       this.button1.Size = new System.Drawing.Size(75, 23);
       this.button1.Text = "Click!";
       this.Controls.Add(this.button1);
       this.button1.Click += new EventHandler(this.button1_Click);

       this.Text = "ThreadException";
       this.ResumeLayout(false);
    }

    // Throw an exception when the button is clicked.
    private void button1_Click(object sender, System.EventArgs e)
    {
       throw new ArgumentException("The parameter was invalid");
    }

    public static void Main()
    {
       // Add the event handler.
       Application.ThreadException += new ThreadExceptionEventHandler(CustomExceptionHandler.OnThreadException);

       // Start the example.
       Application.Run(new ErrorForm());
    }
 }

 // Create a class to handle the exception event.
 internal class CustomExceptionHandler
 {
     // Handle the exception event
    public static void OnThreadException(object sender, ThreadExceptionEventArgs t)
    {
       DialogResult result = ShowThreadExceptionDialog(t.Exception);

       // Exit the program when the user clicks Abort.
       if (result == DialogResult.Abort)
          Application.Exit();
    }

    // Create and display the error message.
    private static DialogResult ShowThreadExceptionDialog(Exception e)
    {
       string errorMsg = "An error occurred.  Please contact the adminstrator " +
            "with the following information:\n\n";
       errorMsg += string.Format("Exception Type: {0}\n\n", e.GetType().Name);
       errorMsg += "\n\nStack Trace:\n" + e.StackTrace;
       return MessageBox.Show(errorMsg, "Application Error",
            MessageBoxButtons.AbortRetryIgnore, MessageBoxIcon.Stop);
    }
 }

Remarks

A ThreadExceptionEventArgs is created by a thread when an unhandled exception occurs. ThreadExceptionEventArgs contains the Exception that occurred.

Constructors

ThreadExceptionEventArgs(Exception)

Initializes a new instance of the ThreadExceptionEventArgs class.

Properties

Exception

Gets the Exception that occurred.

Methods

Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetType()	Gets the Type of the current instance. (Inherited from Object)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)

Applies to

See also

• Thread
• ThreadStart
• ThreadExceptionEventHandler