Question

I am developing Windows Phone 7 Silverlight Application. I want to do Application Level error handling instead of writing try…catch… in all methods. I need to extract Method Name, Class Name and Line Number where the actual error occurred. Below is the demo code. In Application_UnhandledException event, I am expecting Method = “GenerateError” and Class = “ExceptionTesting”. Also, I want to get LineNumber where the actual error occurred (this is not shown in code).

Code to generate Error:

public partial class ExceptionTesting : PhoneApplicationPage  
{
    // Generate Error to Test Exception Handling
    private void GenerateError()
    {
        Int16 i = Convert.ToInt16("test");
    }
}

Code that Handles Application Level Exception:

// Code to execute on Unhandled Exceptions
private void Application_UnhandledException(object sender, ApplicationUnhandledExceptionEventArgs e)
{
StackTrace st = new StackTrace();

var query = st.GetFrames()         // get the frames
        .Select(frame => new
        {                   
            Method = frame.GetMethod(),
            Class = frame.GetMethod().DeclaringType
        });

foreach (var q in query)
{
    if (q.Method.Name.Contains("GenerateError"))
    {
        MessageBox.Show("Class: " + q.Class + ", Method: " + q.Method);
    }
}

if (System.Diagnostics.Debugger.IsAttached)
{
    // An unhandled exception has occurred; break into the debugger
    System.Diagnostics.Debugger.Break();
}
}

Answer 1

The Application_UnhandledException method is not called from your method where the exception happens, so new StrackTrace() will not be meaningful, as you have discovered.

To get the stack trace for the place where the exception occurred, use e.Exception.StackTrace.
Note that the real exception may be wrapped inside another exception, possibly several layers deep (e.Exception.InnerException).