Solved

Call Control from master page using OnError method

Posted on 2007-11-16
7
1,598 Views
Last Modified: 2013-12-17
I am using VS 2005. I have a web page designed using Ajax and ASP.NET , VB.Net is code behind.
In my master page I have a panel that visible property is set to false. In this panel i have a message I want to display when an error occurs in my application.
E.G. List.aspx page - To catch the error i have a method

Protected Overrides Sub OnError(ByVal e As System.EventArgs)
        MyBase.OnError(e)

        '    'do stuff here
        UpdatePanel1.Visible = False

        CType(Me.Form.Parent.FindControl("ErrorHandlerPanel"), Panel).Visible = True ' This is the panel on my master page
       
        Response.Write(Server.GetLastError().Message)

        Server.ClearError()

    End Sub

To test this in my application I have added Throw New ApplicationException("Blahh") on my page load event.

All thats displayed is "Blahh" . Would anyone know how to display my panel from my master page?

However, if I remove Throw New ApplicationException("Blahh") and add CType(Me.Form.Parent.FindControl("ErrorHandlerPanel"), Panel).Visible = True into the onLoad event, it will display fine.
It just seems that the problem is getting the panel to display from the onError method.

Any ideas?
0
Comment
Question by:caoimhincryan
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 3
7 Comments
 
LVL 6

Expert Comment

by:ventaur
ID: 20298797
You cannot call Response.Write in your method. Doing so will usually wipe out your controls and mess up the rendering of the page.

If you'd like to show the message inside your panel, try this instead. You could even put this in the master page instead.
Protected Overrides Sub OnError(ByVal e As System.EventArgs)
  MyBase.OnError(e)
  
  ...
 
  ' Get the error panel from the master page.
  Dim ErrorPanel As Panel = CType(Me.Form.Parent.FindControl("ErrorHandlerPanel"), Panel)
  
  ' Add the error message to the panel and show it.
  Dim ErrorMessage As New LiteralControl(Server.GetLastError().Message)
  ErrorPanel.Controls.Clear()
  ErrorPanel.Controls.Add(ErrorMessage)
  ErrorPanel.Visible = True
 
  Server.ClearError()
End Sub

Open in new window

0
 

Author Comment

by:caoimhincryan
ID: 20299027
Hi Ventaur,

Thanks for the quick response.

However all that is displaying is a blank screen.

Any ideas?
0
 
LVL 6

Accepted Solution

by:
ventaur earned 500 total points
ID: 20299331
I see now. That's apparently by design, because the exception stops code execution, which prevents controls from being rendered (Page and MasterPage included).

Your best bet will be to use custom errors and create a default error page. You can set that up in your web.config file. Otherwise, I think you may be out of luck with your design.
<customErrors mode="On" defaultRedirect="ErrorPage.aspx" />

Open in new window

0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 

Author Comment

by:caoimhincryan
ID: 20299418
I agree with you ventaur. I will leave the question open another while to see if anyone has other ideas for the question.
0
 
LVL 6

Expert Comment

by:ventaur
ID: 20299444
Understood. Good luck!
0
 
LVL 33

Expert Comment

by:raterus
ID: 20299784
Are your users going to debug and fix your application?  They why display the error message to them?  I personally email errors to the programmers, and redirect the user to a basic page saying "whoops".
0
 

Author Comment

by:caoimhincryan
ID: 20311169
I thought maybe with Ajax that it might be possible instead of an error page. Error page is the way to go.
0

Featured Post

Enroll in June's Course of the Month

June’s Course of the Month is now available! Experts Exchange’s Premium Members, Team Accounts, and Qualified Experts have access to a complimentary course each month as part of their membership—an extra way to sharpen your skills and increase training.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Parsing a CSV file is a task that we are confronted with regularly, and although there are a vast number of means to do this, as a newbie, the field can be confusing and the tools can seem complex. A simple solution to parsing a customized CSV fi…
International Data Corporation (IDC) prognosticates that before the current the year gets over disbursing on IT framework products to be sent in cloud environs will be $37.1B.
There are cases when e.g. an IT administrator wants to have full access and view into selected mailboxes on Exchange server, directly from his own email account in Outlook or Outlook Web Access. This proves useful when for example administrator want…
Monitoring a network: how to monitor network services and why? Michael Kulchisky, MCSE, MCSA, MCP, VTSP, VSP, CCSP outlines the philosophy behind service monitoring and why a handshake validation is critical in network monitoring. Software utilized …

734 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question