Displaying the procedure or sub where a error occurs to a user.

Is there a way to display the name of the routine where an error occurs in my code using the framework Obviously, I could put the name of each routine in a message and so forth but that is just a bad design. I was hoping that I would be able to use Reflection or Exception handling to do this in a structured way.

I have several applications that are monitored by IT professionals internal to the company who need as much information as possible about an error that occurs when support is not immediately available. Also there are reporting considerations for tracking the errors.

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Displaying the procedure or sub where a error occurs to a user.

Carlos Hdez
The following example may help.

Create a console application and paste this code in.

Module Module1

Sub Main()
Foo.xyz()
End Sub

End Module

Public Module Foo
Public Sub xyz()
Try
Throw New Exception("ffff")

Catch ex As Exception
MsgBox(ex.TargetSite.ReflectedType.FullName.ToString & " Function:" & ex.TargetSite.Name.ToString)
End Try
End Sub
End Module
Chrisql

I alway do my messageboxes like this:

Try

code......

catch e as exception

msgbox("Exception" & e.message,MsgBoxStyle.Information,"ReadRow - I/O Error")

End Try....

Where the routine name is ReadRow
Pat Backowski

Also check out the Application.ThreadException event.

and Exception.StackTrace
jornjorn

(source code with test app here)

I have this component I put on my main forms to trap all unhandled errors using the Application.ThreadException event-

1.1 code but it compiles in 2.0

create a new class library project call it ErrorTrap.

add references to System Windows.Forms and System.Drawing

add a new form called error form put this code in it (again this is 1.1 code - download the source and convert for 2.0)

Imports System.Windows.Forms

Public Class ErrorForm
    Inherits System.Windows.Forms.Form

    #Region " Windows Form Designer generated code "

    Public Sub New()
        MyBase.New()
        InitializeComponent()
    End Sub

    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    Private components As System.ComponentModel.IContainer

    Friend WithEvents details As System.Windows.Forms.TextBox
    Friend WithEvents message As System.Windows.Forms.TextBox
    <System.Diagnostics.DebuggerStepThrough()> _
    Private Sub InitializeComponent()
        Dim resources As System.Resources.ResourceManager = _
            New System.Resources.ResourceManager(GetType(ErrorForm))
        Me.Button1 = New System.Windows.Forms.Button
        Me.Label1 = New System.Windows.Forms.Label
        Me.GroupBox1 = New System.Windows.Forms.GroupBox
        Me.details = New System.Windows.Forms.TextBox
        Me.message = New System.Windows.Forms.TextBox
        CType(Me.EventLog1, System.ComponentModel.ISupportInitialize).BeginInit()
        Me.GroupBox1.SuspendLayout()
        Me.SuspendLayout()
        '
        'Button1
        '
        Me.Button1.DialogResult = System.Windows.Forms.DialogResult.Cancel
        Me.Button1.Location = New System.Drawing.Point(376, 312)
        Me.Button1.Name = "Button1"
        Me.Button1.Size = New System.Drawing.Size(62, 27)
        Me.Button1.TabIndex = 0
        Me.Button1.Text = "&Ok"
        '
        'Label1
        '
        Me.Label1.AutoSize = True
        Me.Label1.Location = New System.Drawing.Point(12, 19)
        Me.Label1.Name = "Label1"
        Me.Label1.Size = New System.Drawing.Size(61, 16)
        Me.Label1.TabIndex = 2
        Me.Label1.Text = "Description"
        Me.Label1.TextAlign = System.Drawing.ContentAlignment.MiddleRight
        '
        'GroupBox1
        '
        Me.GroupBox1.Controls.Add(Me.details)
        Me.GroupBox1.Location = New System.Drawing.Point(12, 55)
        Me.GroupBox1.Name = "GroupBox1"
        Me.GroupBox1.Size = New System.Drawing.Size(452, 247)
        Me.GroupBox1.TabIndex = 3
        Me.GroupBox1.TabStop = False
        Me.GroupBox1.Text = "Detailed Information"
        '
        'details
        '
        Me.details.BackColor = System.Drawing.SystemColors.Control
        Me.details.Dock = System.Windows.Forms.DockStyle.Fill
        Me.details.Location = New System.Drawing.Point(3, 16)
        Me.details.Multiline = True
        Me.details.Name = "details"
        Me.details.ReadOnly = True
        Me.details.ScrollBars = System.Windows.Forms.ScrollBars.Both
        Me.details.Size = New System.Drawing.Size(446, 228)
        Me.details.TabIndex = 3
        Me.details.Text = ""
        Me.details.WordWrap = False
        '
        'message
        '
        Me.message.Location = New System.Drawing.Point(75, 16)
        Me.message.Name = "message"
        Me.message.ReadOnly = True
        Me.message.Size = New System.Drawing.Size(381, 20)
        Me.message.TabIndex = 2
        Me.message.Text = ""
        '
        'ErrorForm
        '
        Me.AcceptButton = Me.Button1
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.CancelButton = Me.Button1
        Me.ClientSize = New System.Drawing.Size(468, 352)
        Me.Controls.Add(Me.message)
        Me.Controls.Add(Me.GroupBox1)
        Me.Controls.Add(Me.Label1)
        Me.Controls.Add(Me.Button1)
        Me.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog
        Me.MaximizeBox = False
        Me.MinimizeBox = False
        Me.Name = "ErrorForm"
        Me.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen
        Me.Text = "Application Exception"
        CType(Me.EventLog1, System.ComponentModel.ISupportInitialize).EndInit()
        Me.GroupBox1.ResumeLayout(False)
        Me.ResumeLayout(False)
    End Sub

    Friend WithEvents Button1 As System.Windows.Forms.Button
    Friend WithEvents GroupBox1 As System.Windows.Forms.GroupBox
    Friend WithEvents Label1 As System.Windows.Forms.Label
    #End Region

    Private _exception As Exception
    Public Sub Display(ByVal ex As Exception)
        _exception = ex
        Me.ShowDialog()
    End Sub

    Protected Overrides Sub OnLoad(ByVal e As System.EventArgs)
        Me.Text = String.Format("{0} - {1}", Me.Text, Application.ProductName)
        message.Text = _exception.Message
        details.Text = String.Format("{1} - {2} {0} at: {3}.{4}{0}Stack trace:{0}{5}", _
            System.Environment.NewLine, _
            _exception.GetType().Name, _exception.Message, _
            _exception.TargetSite.ReflectedType.Name(), _
            _exception.TargetSite.Name, _exception.StackTrace)
        MyBase.OnLoad(e)
    End Sub
End Class

Public Class ExceptionHandler
    Inherits System.ComponentModel.Component

    Private components As System.ComponentModel.IContainer
    Private _ThreadExceptionArgs As System.Threading.ThreadExceptionEventArgs
    Public Event ExceptionHandled As Threading.ThreadExceptionEventHandler

    Public Sub New(ByVal Container As System.ComponentModel.IContainer)
        MyBase.New()
        Container.Add(Me)
        If DesignMode Then Exit Sub
        AddHandler Application.ThreadException, AddressOf Me.ExceptionHandler
    End Sub

    <System.Diagnostics.DebuggerStepThrough()> _
    Private Sub InitializeComponent()
        components = New System.ComponentModel.Container
    End Sub

    Public Sub New()
        If DesignMode Then Exit Sub
        AddHandler Application.ThreadException, AddressOf Me.ExceptionHandler
    End Sub

    Private Sub ExceptionHandler(ByVal sender As Object, _
                ByVal t As System.Threading.ThreadExceptionEventArgs)
        _ThreadExceptionArgs = t
        Dim ef As New ErrorForm
        Try
            ef.Display(t.Exception)
            Me.OnExceptionHandled()
        Catch ex As Exception
            MessageBox.Show("Fatal Error", "Fatal Error", MessageBoxButtons.OK, _
                    MessageBoxIcon.Error)
        Finally
            ef.Dispose()
        End Try
    End Sub

    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If Not DesignMode Then _
            RemoveHandler Application.ThreadException, _
                AddressOf Me.ExceptionHandler
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    Protected Overridable Sub OnExceptionHandled()
        RaiseEvent ExceptionHandled(Me, _ThreadExceptionArgs)
    End Sub
End Class

you can add ExceptionHandler to your toolbox and drop it on your main form to trap all unhandled errors. It displays the Message as well as detailed Exception information - TargetSite and Stack trace.

source code with test app here
theprogrammer
Is there a way to use the framework to return the routine name
programmatically

Try

code.....

catch e as exception

msgbox("Exception: " & e.message, MsgBoxStyle.Information, Function())

End Try...
Displaying the procedure or sub where a error occurs to a user.

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