Question

In the following code an exception is thrown in Inner_A(x). How do I show in the stack trace what the value of x was as the stack trace looks like this:

at Default2.Inner_A(String x) in C:\test1\Default2.aspx.vb:line 25
at Default2.Page_Load(Object sender, EventArgs e) in C:\test1\Default2.aspx.vb:line 12






Dim strErrorMesssage As String

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    Try
        Dim x As String = "testvar"

        Inner_A(x)
    Catch ex As Exception

        strErrorMesssage &= DirectCast(ex, System.ApplicationException).StackTrace.ToString()

    End Try


End Sub


Private Function Inner_A(ByVal x As String) As String

    Throw New ApplicationException("Exception Occured caused in INNER_A ")

    Return " Function Inner_A"

End Function

Answer 1

You can’t modify the stack trace, but you can include the value of the variable in your error message:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    Dim x As String
    Try
        x = "testvar"

        Inner_A(x)
    Catch ex As Exception
        strErrorMesssage &= "X = " & x & Environment.NewLine & DirectCast(ex, System.ApplicationException).StackTrace.ToString()
    End Try
End Sub