Ways To Identify A Particular Exception From Exception Class?
May 18, 2010
Is there any way to uniquely identify a particular exception from the general exception class.
i.e any property or method that retrieves a unique identifier that to identify a particular exception.
I have kept some error values and corresponding error texts in an xml file. I want to read that xml file and have to taken the error ids and fix the corresponding texts to a label. in the case of a system exception we have to identify a particular exception.
In ASP.NET,How can i know the Specific details about an exception (like What kind of Exception it is (FileNotFound /Arithmentc etc..) )from a General Exception class object.
I am working on a 3-tier asp.net application. Currently I'm stuck up in a situation where I need to handle a specific type of exception (User Defined) in DAL and Show alert to the user if that exception occurs in DAL.
I tried following things:
1) I raised that exception from the DAL and catch it in BLL and throw a new BLL exception to for that DAL exception and finally catch it in the UI layer to show the alert to the user. I've successfully implement this in my project. But there are some issues in this approach. First of all I feel this is not right way to do this as it may lead to performance related issues. Secondly, the application contains more than 500 pages and classes. so I need to attach additional catch block in every method to catch the BLL exception. which is the last option i'd like to take.
2) in second approach I logged the the DAL exception into a text file. but problem in this approach is that how could the UI layer know that exception has occurred and show the alert to the user. Is there any event in asp.net where i could handle all this activities?
my question is what is the best approach to handle this type of situation? Will Exception handling block help me in this?
I've tried reading many articles on this but i couldn't get an answer for my question? I might not be using right keywords for my search.
3. Data Access Layer to do the dealing with the database.
Now i have a Contacts page from where i can add a new contact to the database.So to add a New Contact i fill in all the required details and then call a Add Method (residing in the BLL) from the page, which in turn call a Add Method residing in the DAL.this method in the DAL returns the Current Identity of the record which is then return back to the BLL method and finally delivered on the page.this is fine. but what if a get an exception how do i handle it properly because the method in DAL has a return type of int and i dont want to throw another error!! coz other wise i will have to write try catch in almost all the methods.
//something like this public int AddMethod(ContactClass contactObj) { int result = 0;[code]...
rather i want to show the user a user-friendly message which they can easily understand and in the mean while i will send a mail to myself documenting the Error that just occurred.how can i implement my custom exception classes.
We're getting this InternalSubStringWithChecks exception with our application's healthMonitoring. This exception is like the Padding is invalid and cannot be removed exception where it's being recorded and we're getting a notification email but the end user is unaware that an actual error has happened. Though we don't want our event log filled up with this rubbish! The stack trace is:
Parameter name: length at System.String.InternalSubStringWithChecks(Int32 startIndex, Int32 length, Boolean fAlwaysCopy) at System.Web.Handlers.AssemblyResourceLoader.System.Web.IHttpHandler.ProcessRequest [code]...
I have simple 3 tier web application and have mostly CRUDE functionalities. Recently I required to add new console application to the existing solution in which I call data layer methods for retrieving data from DB but I get an exception "The type initializer for threw an exception."When I debugged I found that the exception is thrown at datalayer on first line of class where I get connectionstring from
web.config, the code is public static readonly string CONNECT_STRING =
Now if I hardcode the connection string value like public static readonly string CONNECT_STRING = "Data Source=XYZ;uid=sa;password=XXX;initial catalog=ABC;"
it works fine.I don't understand what is the issue here as web application works fine with this datalayer.
I am part of a team that is developing a SharePoint web part. My task is to create a user control which will ultimately be wrapped in another class for presentation in a web part. Because of these requirements, I must fit all of my code in a single user control.To organize my code in the code-behind, I created a few private classes for the different objects which are represented in the database. I want to add some exception handling whereby if some sort of DB exception is thrown I can update a message on the page informing the user of the problem.
My problem is that the page-level controls are inaccessible from the private class where I'm issuing the query, so even if I catch the exception I have no way of directly accessing a Label control to populate the error. I tried to create a baseclass with an EventHandler defined, but when I throw events from the private class I'm not able to catch them for whatever reason. I'm far from an OOP expert Here is a snippet: ASP Code: using System; using System.Collections; [code]....
When I get an exception message like this I want an Exception Class name to compare.Not wantto compare a string to match with substring.when I get an unique constraint error like this below how can I control if error exception type is exactly sqlserver unique constraint error ?:
catch (Exception ex) { if (ex.class==SQLUniqueException) blahblah(); };
In our application we have to access session objects in business class. We are using HttpContext.Current.Session to get the session value. In some cases it returns the value but mostly its throwing a null reference exception(Object reference not set to an instance of an object). We have the following code Try
If HttpContext.Current.Session("Username") IsNot Nothing then ' Statements to be executed End If Catch ex As Exception 'Log to db End Try
Here HttpContext.Current.Session("Username") is mostly throwing an exception "Object reference not set to an instance of an object" While debugging we found that HttpContext.Current itself is nothing.
I have an asp button which I am using in 2 different places (appending to a new place and adding a class using jquery under certain conditions). I need to slightly alter the function that runs when this button is clicked depending on whether or not this button has a given class. Is this possible??So something like this...
In general I want to know what is the difference between bug and exception? If I need to be specific for a particular framework then I would like to go with .Net.
Panel pnl_Confirmation = (Panel)form1.FindControl("ConfirmationPanel") as Panel; pnl_Confirmation.Visible = false;
I keep getting a "NullReferenceException" in the above code. "ConfirmationPanel" is a panel I show/hide depending on if the form is submitted successfully or not.
The panel is wrapped in a LoginView control, which is why I cannot call "ConfirmationPanel" directly:
I created a simple data access layer in the dll and reference it in my web app. How can I point the error to the user that his code in this line has an exception. currently, when i input a nonexisting table it will popup an error "invalid object name table_name" and points the my code throw exception inside my dll. I want it to point out to the user code that uses my function that creates an error.
Line 92: Dim ds As DataSet = DAL.Dal.ExecuteDataset("SELECT * FROM table_nam", "DBConnectionString")
I am trying to catch an exception but occasionally get an inner exception. I want to output both into a label. I often get Object reference not set to instance of an object if there is no inner exception.
Catch ex As Exception exError = ex.Message.ToString If Not ex.InnerException.Message Is Nothing Then exError &= "<br/>" & ex.InnerException.Message.ToString End If Return View() End Try
As far as I can see, whenever a filter's OnActionExecuted is called, it might be after an exception has been thrown futher down the request processing pipeline. So surely this means that one should always be checking to see if there's an exception in the filter's context within an implementation of OnActionExecuted?
Isn't this like pre-exceptions error handling where one would have to, say, check the result of a method call to determine if there'd been an error - of course opening up the possiblity that one might forget to do this?
I'm handling exceptions in the Application_Error() method in Global.asax but ex.Source is not giving me much. I want to know where the error occured i.e. /folderName/pageName.aspx.
Also I use lots of user controls so getting aspx name may not even be enough. Is there a way to get the name of object where the exception occured i.e. class name, user control name, etc.
What is the point of throwing an exception? It it anyways going to be caught in the Global.asax Application_Error method.
Lets say in the following code we throw an exception.
try { using (var dc = GetDataContext()) { // We are doing some data inserts here. } catch ( Exception ex) { throw ex; }
My Question: Even if we do not use try catch and throw here, any exception which will be raised here will be caught inside Application_Error method in Global.asax. Then what is the point of try, catch and throw in this case?
