Which Is Faster - A Using Block Or Try / Catch / Finally

Sep 2, 2010

This is a followup question to this Should I stick with the Try/Catch/Finally construct, or go with the Using construct? Sample Code for Try/Catch/Finally:

[Code]...

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Catch Exceptions In Finally Block?

Oct 13, 2010

Is there some special way to catch exceptions in finally block ?

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C# - Use Case For Try-catch-finally With Both Catch And Finally

Feb 17, 2010

I understand how try-catch works and how try-finally works, but I find myself using those (usually) in two completely different scenarios:

try-finally (or using in C# and VB) is mostly used around some medium-sized code block that uses some resource that needs to be disposed properly.
try-catch is mostly used either

around a single statement that can fail in a very specific way or (as a catch-all) at a very high level of the application, usually directly below some user interface action.

In my experience, cases where a try-catch-finally would be appropriate, i.e., where the block in which I want to catch some particular exception is exactly the same block in which I use some disposable resource, are extremely rare. Yet, the language designers of C#, VB and Java seem to consider this to be a highly common scenario; the VB designers even think about adding catch to using.

Or am I just overly pedantic with my restrictive use of try-catch?

EDIT: To clarify: My code usually looks like this (functions unrolled for clarity):

Try
do something
Aquire Resource (e.g. get DB connection)
Try

[Code]....

which just seems to make much more sense than putting any of the two catches on the same level as finally just to avoid indentation.

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If Throw An Exception From Within A Catch, Does The Finally (from The Catch) Still Execute

Jun 2, 2009

If I throw an exception from within a catch, does the finally (from the catch) still execute? i.e.

Try
..some code with an exception in it...
catch ex as Exception
throw new SpecialException("blah blah" & ex.Message, ex)

[code]....

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Why Use Finally In Try/Catch

Nov 25, 2009

OK, I'd like to know the difference between the following two blocks of code:

Block A
Try
Something

[code].....

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Use Finally In A Try Block?

Apr 3, 2010

I often use the Try block to catch exeptions, and I have read in the help pages to do with the Finally statement. But, from what I understand it has no use whatsoever. Why would I use Finally instead of just ending the Try block. For example, from what I know

[Code]...

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C# :: Why Can't Write Just A Try With No Catch Or Finally

Dec 27, 2010

Sometimes I do this and I've seen others doing it too:

VB:
Try
DontWannaCatchIt()

[code].....

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Set An Object To Nothing In The Finally Block?

Apr 4, 2012

In this VB.NET code:

Dim o as SomeClass
Try
o = new SomeClass
'call some method on o here
Catch(...)

Why is there a need to set o to Nothing? What if i don't set it to Nothing in the Finally block? What i think is that it is OK if you don't set it to Nothing because the object will be marked for GC.

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Return Inside Try/catch/Finally?

Sep 15, 2009

I have a (begginner) question on VB.NET. Is this good code (I mean, is it "bullet proof")?. It seems to work, but I understand the Return is executed AFTER the Finally. So how does it call a method on an allready disposed of object?

[Code]...

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Try Catch Finally Doesn't Work?

Mar 23, 2010

I've a class with a timer inside

Private tt As New System.Timers.Timer()
This timer is enabled in the New() of the class
Try

[code].....

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VS 2008 How To Use Try Catch Finally Statement

Jun 15, 2009

i want to know how to use try catch finally statement.i want to catch this error Violation of PRIMARY KEY constraint 'XPKemployee'. Cannot insert duplicate key in object 'dbo.employee'.

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VS 2008 How To Use Try..Catch...Finally Statement

Mar 4, 2011

i have this problem about the try,catch,finally statement... i don't know how to use it..i have my converter program here and this should be type by a letter 'cause if you do it will go lag or hang...i try VERIFY button to make sure if it's a letter or number but my teacher said it's not counted...

Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
If ComboBox1.Text = "Pounds To Kilo" Then

[code]....

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.net - Replicate Try/catch/finally Using On Error Goto

Jun 14, 2012

Suppose in VB.NET you have:

Try
Debug.Print("Trying...")
Catch ex as Exception
throw new Exception("Exception", ex)
Finally
Debug.Print("Finally...")
End Try

How would you write this using the "On Error Goto" construct? (please no questions asking why I would want to do this, just curious if it can be done).

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Trap Any Exceptions With Try Catch Finally If The Reader?

Apr 8, 2011

I have a SqlDataReader and I want to trap any exceptions with Try Catch Finally if the reader =cmd.ExecuteReader() statement fails. If this statement throws an exception do I need to close the reader? If so, where. Wherever I place the reader.close() statement I get an error that the reader has not been assigned a value yet.

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C# - .NET Will Stop Debugging Run The Code In The Finally Block?

Jun 18, 2012

Well, I've read (and learned) that the finally block doesn't always execute its code (even apart from pulling the plug).FYI For more information, see try catch finally question

[Code]...

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IDE :: In Finally Block - Check If An Exception Occurred Or Not ?

Sep 18, 2011

In Finally Block, How can we check if an exception occurred or Not.I am programming in VB.Net. Why i am asking is that in the Finally Block there could be some things you would like to do if an Exception has occured and some things you want to do if an exception has not occured. So, within finally block how do we know if an exception has occured

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Null Reference Exception In Finally Block

Jul 2, 2009

does any one know the reason of why I get Warning in the Finally block in vb.

[Code]...

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Within The Finally Block, Check If An Exception Occurred Or Not ?

Sep 18, 2011

I am Not using the "Catch Ex as Exception" for some of my application's architect details.So, if my code is something like

Try
'code here
Catch ex As ApplicationException '!!! i.e. ApplicationException

[code]....

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.net - Try Catch Finally Blocks.. Do I Still Need Them When Handling Errors In The Global.asax

Jun 2, 2010

I am handling errors via my global.asax in this method:

Dim CurrentException As Exception
CurrentException = Server.GetLastError()
Dim LogFilePath As String = Server.MapPath("~/Error/" & DateTime.Now.ToString("dd-MM-yy.HH.mm") & ".txt")
Dim sw As System.IO.StreamWriter = New System.IO.StreamWriter(LogFilePath)

[code]....

In my code I currently have no other error handling. Should I still insert try, catch, finally blocks?

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Is Try / Catch / Finally Required With Using Statement In Order To Handle Exceptions

Jan 31, 2012

I wonder how to use statement handles exceptions?Do I need to wrap the using statements with a Try/Cath/Finally clause in order to be sure that the SqlConnection object is closed and disposed even if the containing code throws an exception? [code]

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Sql - Use A Try And Catch Block In .net?

Mar 19, 2011

For the code shown below, how would I use a try/catch block to handle an error if it were to occur?

TOTKILO.Text = KILO.Text * TOUCH.Text * 0.01
TextBox10.Text = TextBox9.Text * TextBox8.Text * 0.01
K = Math.Round(Val(TOTKILO.Text) - Val(TextBox10.Text), 5)

[code]....

I used VB.Net controls and LINQ to SQL to perform all Updates and Inserts, so when an error occurs I want to show "Enter Data Correctly", how do I do that once I catch an exception?

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Asp.net - Catch Block Not Catching?

Aug 8, 2011

I have a simple function which tries to get a value from an Obout grid filter column, and if the value is empty, ignores it and moves on. For some reason this code ignore my catch block and always shows a System.FormatException when the input string is empty More bizarre, if I use visual studio's debugger and set a breakpoint on that line, the catch block functions normally (after I continue from that line). I have already confirmed that my Debug | Exceptions | CLR are not set to catch when thrown. I have also confirmed this same behavior in the production version.

[Code]...

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Return Value From A Try Catch Block?

Mar 1, 2009

how do i make sure -1 is returned if an error occored?

Public Function ExcecuteNonQry(ByVal sql As String, Optional ByVal connectionString As String = "")
Dim returnVal As Integer = -1

[Code].....

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Asp.net - Try-catch Block Still Be Throwing An Error?

Apr 23, 2010

Why would my try-catch block still be throwing an error when it's handled?[code].......

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WebException Not Caught In Try/catch Block?

Feb 3, 2011

I've tried to Google this problem, but haven't found any relevant results.I am trying to handle HTTP 500 errors when logging into a web service (the web service returns 500 when login is incorrect). An WebException is thrown, but I can't seem to catch it properly. The exception is highlighted in green instead of the normal yellow (having trouble finding info on this as well)

[Code]...

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Add A Block Of Xml Comment And Create A Try-catch To A Function?

Jul 7, 2011

We've created a little plugin to add a block of xml comment and create a try-catch to a function. (we simply add this to each and every function we write).But with the latest devexpress update I'm having a problem with the following code.[code].........

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C# - GridView SelectedIndexChange With Try Catch Block Faulty In 2.0?

Dec 14, 2009

I am using ASP.NET 2.0. When i place a TRY CATCH block in my event it always go into the CATCH section, in my case it re-direct the page to Default.aspx. But if I remove the TRY CATCH block the code get's executed fine and it does what it suppose to.

CODE:

There is no error message when i place a break point by the "Catch ex As Exception" Am I reading the selectedRowIndex DataKey value incorrectly maybe?

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Change The Auto-fill On Try Catch Block In .net?

May 1, 2011

In visual studio when I type the word try it automatically adds the catch and and try for me.

I want to add after the catch something like Msgbox(ex.message)... I'm tired to type the same thing over and over.

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MDI Global Error Handling - Nothing In Try Catch Block

Nov 21, 2008

I normally use the following for global error handling:
Code:
Dim currentDomain As AppDomain = AppDomain.CurrentDomain
AddHandler currentDomain.UnhandledException, AddressOf MYExceptionHandler
AddHandler Application.ThreadException, AddressOf MYThreadHandler
I normally don't have a MDI application, and When I force an error, neither of the events get fired. I don't have anything in a try catch block. How do I do this with a MDI application?

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Null Reference Exception In Catch Block

Oct 18, 2011

I'm trying to catch an invalid entry in a textbox that I use to enter numbers using the subroutine below.

In the Catch blok I want to change the ForeColor of the textbox that contains the invalid entry.

This did function but now gives me a null reference exception on the line where I change the ForeColor.

Private Sub SaveParm()
Dim Temps(2, 2) As Double
Dim Cname As String = "Text0"

[Code]......

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