CODEWITHSUNDEEP
c#winformsexception
Pankaj
Pankaj

Reputation: 1524

Global level error handling in C# windows application

I am trying to implement global level error handling in my windows application

I have the button click event for the form which creates some error

  label1.Text =
            class1.Calculate(Convert.ToSingle(textBox1.Text), Convert.ToSingle(textBox2.Text))
                  .ToString(CultureInfo.InvariantCulture);

        MessageBox.Show("That was really Close");

now I want the control to go to message box, the unhandled error are being handled in the main function as 

private static void Main()
    {

        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.ThreadException += new ThreadExceptionEventHandler(Application_ThreadException);
        Application.Run(new Form1());
    }
    private static void Application_ThreadException(object sender, ThreadExceptionEventArgs e)
    {
        if (e.Exception.InnerException != null)
            MessageBox.Show(e.Exception.InnerException.Message.ToString());
        else MessageBox.Show(e.Exception.ToString());
    }

This code sample does handles the exception but I want the control back to the button Click, that is The MessageBox.Show("That was really Close"); should get called after exception handling

Upvotes: 1

Views: 2576

Answers (1)

Chris
Chris

Reputation: 27629

If you don't want the method to stop on an exception then you need to handle the exception at that point. You could have the catch call some kind of global error handling method but you will need a try catch in that method.

Global level exception handling is for exceptions that you can't deal with immediately and need to catch before the program dies, usually for logging and such like.

Global level exception handling is not a substitute for handling exceptions at the correct place. If you expect code to throw an exception and it is one you can deal with then you should put a try/catch at that point of the code. In the example above you say you want to carry on running the method so clearly the error is not a fatal one so you should deal with it in the normal way.

Often though it should be noted that exceptions that you can handle are ones that can be avoided. For example checking what you pass to a method before passing it. The ones that can't be removed entirely are usually ones to do with external resources (eg reading files). I'm sure there are a lot of other exceptions but as somebody wise once said "Exceptions are for exceptional circumstances". If you can foresee them you should try to avoid them.

In this case I assume the exception is related to invalid input in your text boxes. In this case you should use Single.TryParse to verify the input before passing it on to your method. If either of the values fails to parse you can then let the user know that properly.

Upvotes: 2

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