Confusion between global.asax setting and web.config [Archive]

expectomas

06-09-2011, 08:39 PM

Good Day to everyone,

I am kind of confused between the settings of global.asax and web.config.

As I understand that by catching http-related exceptions in global.asax, I can use server.transfer(url) to 'redirect' to respective error page.

In view of this, does the web.config error page configuration still necessary. i.e. if I were to 1) remove redirection from web.config error redirect or 2) set custom mode to 'off' i can still transfer users to an NotFound (404) error page.

Thank You

bruce

06-10-2011, 11:40 AM

If you have exception management in the global.asax which redirect to an error page, the ASP.NET customer error will not take effect as the error is technically captured.

Miro

09-10-2011, 11:41 PM

Bruce,

Could you provide an example of the "exception management in the global.asax " ?

I have been playing with a response.redirect and a server.transfer in the global.asax and they dont seem to be working at all.

Thanks,

Miro

wisemx

09-11-2011, 04:23 AM

Scroll down to the global.asax App error section of this page:
http://msdn.microsoft.com/en-us/library/aa479319.aspx

On this page look at the use of HttpContext.Current.Response.Redirect:
http://forums.asp.net/p/1417139/3128537.aspx

Hope those help.

Miro

09-11-2011, 10:22 AM

Thank you bruce,

I read the microsoft link the other night but I was still having problems.

The link you posted: http://forums.asp.net/p/1417139/3128537.aspx gave me the fix I need.

Incase anyone else runs into this ....

I originally had in my global.asax code like this:
(example)
Response.Clear()
Response.Redirect("PageNotFound.aspx")
Response.End()

From the top link I changed it to be:

HttpContext.Current.Server.ClearError()
HttpContext.Current.Response.Redirect("~/PageNotFound.aspx")

and that worked.

======

A dumbed down full snippet for anyone who is having the same problems is like this:

Global.asax

Sub Application_Error(ByVal sender As Object, ByVal e As EventArgs)
' Code that runs when an unhandled error occurs
Dim lastErrorWrapper As HttpException = CType(Server.GetLastError(), HttpException)

HttpContext.Current.Server.ClearError()

If lastErrorWrapper.GetHttpCode() = 404 Then
HttpContext.Current.Response.Redirect("~/Error404.aspx")
Else
Dim lastError As Exception = lastErrorWrapper
If lastErrorWrapper.InnerException IsNot Nothing Then
lastError = lastErrorWrapper.InnerException
End If

Dim lastErrorTypeName As String = lastError.GetType().ToString()
Dim lastErrorMessage As String = lastError.Message
Dim lastErrorStackTrace As String = lastError.StackTrace

CreateHTMLErrorFile(lastErrorTypeName, lastErrorMessage, lastErrorStackTrace)
HttpContext.Current.Response.Redirect("~/ErrorCustom.aspx")
End If
End Sub

Private Sub CreateHTMLErrorFile(ByVal lastErrorTypeName As String, ByVal lastErrorMessage As String, ByVal lastErrorStackTrace As String)
Dim HTML As String = _
String.Format( _
"<html>" & vbCrLf & _
" <body>" & vbCrLf & _
" <h1>An Error Has Occurred!</h1>" & vbCrLf & _
" <table cellpadding=""5"" cellspacing=""0"" border=""1"">" & vbCrLf & _
" <tr>" & vbCrLf & _
" <td style=""text-align: right;font-weight: bold"">URL:</td>" & vbCrLf & _
" <td>{0}</td>" & vbCrLf & _
" </tr>" & vbCrLf & _
" <tr>" & vbCrLf & _
" <td style=""text-align: right;font-weight: bold"">User:</td>" & vbCrLf & _
" <td>{1}</td>" & vbCrLf & _
" </tr>" & vbCrLf & _
" <tr>" & vbCrLf & _
" <td style=""text-align: right;font-weight: bold"">Exception Type:</td>" & vbCrLf & _
" <td>{2}</td>" & vbCrLf & _
" </tr>" & vbCrLf & _
" <tr>" & vbCrLf & _
" <td style=""text-align: right;font-weight: bold"">Message:</td>" & vbCrLf & _
" <td>{3}</td>" & vbCrLf & _
" </tr>" & vbCrLf & _
" <tr>" & vbCrLf & _
" <td style=""text-align: right;font-weight: bold"">Stack Trace:</td>" & vbCrLf & _
" <td>{4}</td>" & vbCrLf & _
" </tr> " & vbCrLf & _
" </table>" & vbCrLf & _
" </body>" & vbCrLf & _
"</html>", _
Request.RawUrl, _
User.Identity.Name, _
lastErrorTypeName, _
lastErrorMessage, _
lastErrorStackTrace.Replace(Environment.NewLine, "<br />"))

Dim path As String = "~/_Database/ErrorLogs/" & DateTime.Now.ToString("yyyymmdd_hhmmss") & ".html"

If Not File.exists(System.Web.HttpContext.Current.Server. MapPath(path)) Then
File.Create(System.Web.HttpContext.Current.Server. MapPath(path)).Close()
End If

Using w As StreamWriter = File.AppendText(System.Web.HttpContext.Current.Ser ver.MapPath(path))
w.WriteLine(HTML)
w.Flush()
w.Close()
End Using
End Sub

=====

My only issue now is - to figure out if I can get the error above to also show the line numbers where the error occured.

Many Thanks,

Cheers'

Miro