Empty Catch In Global.asax To Prevent Exception From Stopping A Web Application?
Sep 28, 2010
I'm using a static Timer in my Global.asax to run a method at regular intervals. When the method throws an exception, my application is stopped. I have used an empty catch to prevent exceptions from stopping the application something like below code. Is there a disadvantage to use such an approach?
If I am just logging exception details in my web app, do I really need to put in exception handling logic for each tier? Why not just let them all bubble up the stack trace to the global.asax and log them there?
I'm trying to use the Global.asax file in the root application of the website to catch requests for pdf files in the root that don't exist any more. I've configured iis to send pdf requests to asp.net. The whole thing works perfectly on development. It also works on the live system with missing .aspx pages, but not .pdf. Instead an "Error Code 64: Host not available". I'm using the Global.asax file to avoid the web.config and child applications (1.1 & 2.0) inheriting settings.
Edit:
I configured IIS to send .pdf requests to asp.net using the Application Configuration dialog on the mappings tab and adding .pdf extension mapped to the aspnet_isapi.dll. "Verify that file exists" is turned off (although I've also tried it turned on).
So I handle all exceptions in my project within my Global.asax page. For example, on a random page I could have:
[code]....
So my question is in the Application_Error method, do I need the try/catch block when trying to write to the database? I'm thinking I would in case something goes wrong with the connection, etc. - but is this really necessary? Also, what would I do in the catch block if there is an error? At that point I would be catching the error of logging an error which is confusing in its own right.
Looking for best practice focused answers here with explanations.
Should the presentation layer of an ASP.Net app catch and handle exceptions thrown from the business layer, or should these be allowed to bubble out, where they can all be logged and handled uniformly in the Global.ascx's Application_Error handler?
I have (pretty much) the following code in my protected void Application_Error(object sender, EventArgs e) method in Global.asax....
Exception ex = Server.GetLastError();
if (ex is System.Security.SecurityException)
Response.Redirect("Logon.aspx");
else
Response.Redirect("ErrorPage.aspx");
If I navigate to a page before I log on the exception is caught and I am redirected to Login.aspx as I would expect. However, this is only working when debugging using VS on my local machine.When uploaded to the live environment, the exception is not caught and the user is presented with "Security Exception - Request for principal permission failed."
I m having a datagrid and for client side events I m using Javascript. I have few other buttons in the same page.
when I click on datagrid and select, it is working fine. After that, if I click on any other button in the Page, It is directly going to global.asax and throwing exception.
If I click directly on other buttons, they are working fine. Once I click on Datagrid and try to click on other buttons, it is throwing that exception.
Here's my problem I have some code and I'm using it to send an e-mail with the last error details but all I want is the (Inner)Exception Message to be displayed in the email with the URL
my objective is i want to log all those exceptions on my aspx pages which are handled or unhandled. To do this do i need to write my method in global.asax or how can i do that?
Question: When a webapplication gets started, it executes Application_Start in global.asax.Now, a web application gets started as soon as the first request for a page in that application reaches the server.But my question is: how long will the application run until the application is stopped.I mean when after the first page request, there's no traffic on the server.I need to know because I intend to start a server that listens on a tcp port in global.asax.And when the application stops, the server ceases to listen to its port.
I am developing my application in asp.net 3.5 and sql server 2005, and I want to record the visitor info into my database, like once the visitor enter my website, I'll insert his browser details to the database. [It's not necessary that visitor login my website].
Now I am confused where to put my code, If I put insert function in every page_load then on every page it will execute and I'll not be able to get the exact number of visitor, visited my website. Shall I go with application_start in Global.asax ??
I'm trying to create Global.asax in a Winform. I could do it in ASP.NET, but i couldn't find a way for Windows Application. I have a singleton class called DataAccessLayer, i need to instantiate it once only, so i can call its method/properties anywhere in the application easily.
I have a need to add an application level event (like Application_Start) but not in global.asax. The reason that I can't use global.asax is because this is a web application for which I don't have source code but I want to add some functionality to it. I need to insert an application start code and was wondering it there was anyway to do it. I'm not sure that if I add a class or aspx page to the sie if it will dynamically compile since this is a web application.
I want to make sure of one thing. I have implemented the Application_Error() method of Global.asax. In my application some where I have a try catch. If an exception is trown and that exception is handled by a catch block. Does this envoke the Application_Error() method in the global.asax
I have existing web application project in which i need to add new subdirectory. In this subdirectory i need to add WCF service.Question is: Can i use different AppDomain then services from root directory? Also, can i add new global.asax just for this subdirectory?
Not using Cassini, but IIS7 to run an ASP.NET app.
The debug behavior is flakey. Sometimes it works, sometimes it doesn't. I was able to step into the application start event in global.asax but sometimes I can't.
Sometimes VS2008 opens the published global.asax so I have two instances of global.asax opened in VS, the source and the published.
I reset the AppDomain and IIS and I can't put my finger on why this is happening.
To add, while it won't go into application start, I have an OnChangeEventHandler event - it does step into the event handler.
I'm working on a new C# web application in Visual Studio 2010, and am having problems reading a value in Web.Debug.Config from the GLobal.asax.cs file.
In the Application_Start event I've got the following code:
When running in debugger, I've got a break-point in the Application_Start event in Global.asax.cs. It hits the break point, but in all cases the value coming back from ConfigurationManager is coming back null. What am I doing wrong?
I know there is a couple answered questions on here regarding "request scoped" globals, but I want to nit-pick on something specifically and maybe squeeze some extra enlightenment out of one or two of you.I have an ASP.NET C# Website and a static Dictionary of objects (loaded from DB once on Application start). Each page request will need to do a lookup in the Dictionary (based on a key derived from the request url/etc) and get the appropriate object.The issue is I'm trying to maximize efficiency by reducing the lookups to the Dictionary per Request. Doing just a single lookup within a Page itself is easy enough and I can pass the object to sub controls, etc too.. but global.asax is separate from the Page and it also needs to use the object (in Application_BeginRequest and Session_Start).
So is doing a Dictionary lookup once in Application_BeginRequest, once (when necessary) in Session_Start and once in the Page negligible speed wise, even if there are many requests coming in every second?I would like it if I could just have a Request scoped global variable that I can easily call upon.. the only one I see available though is HttpContext.Current.Items and that is a Dictionary itself.Am I beingridiculously nit-picky with my concern over efficiency? or will these milliseconds (nanoseconds?) get me in the long run when more and more requests are being made?
PS. I currently only have around 100 objects in the Dictionary although this may increase in the future.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Threading.ThreadAbortException: Thread was being aborted.
Source Error:
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.
I even created a global.asax file and on the Application_Error event, I wrote a code that would email me the error (and i'm not getting an email regarding that error when I get the error shown above). I know for a fact that the thread is going inside the "try" statement because I send emails to myself whenever it finishes certain codes inside of it. So how come I'm getting that error in my browser instead of it being handled in my "catch" statement? I have two problems here, one, why is the exception not going to my "catch" statement, and two, why am I getting that error in the first place.
When debugging my application, I m getting an application level error in global.asax file. The Server.GetLastError() reads "File does not exist." but thats it. No more details on the filename or the location where the code is trying to find a file. I commented out the application_error method, with a hope that the exception would be thrown when the debug the application, but no errors were thrown. How do i find the source of the error, cos I want to resolve this issue by either putting the file that the application is looking for or by completely removing the code that is referencing the file.
Is it possible in the global.asax file on session_start to check if a url string exists and it it does insert the string into a sql database? The url would be something link http://www.mysite.com?campaign=january.
I would want to capture the january bit and put that in the database for each visitor that uses that url.