On Error Goto 0 Asp Classic
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here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring on error goto 0 vbscript developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question on error goto 0 in qtp x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 6.2 million programmers, just like you, helping each other. Join them; asp on error goto label it only takes a minute: Sign up What does the “on error goto 0” and “error resume next” in old ASP mean? up vote 5 down vote favorite I am working with old ASP code and I am not on error goto 0 vba sure about semantics of on error goto 0 and error resume next construction. Can you recommend me some useful resources or enlight me directly? asp-classic vbscript share|improve this question edited Dec 1 '11 at 20:02 Joel Coehoorn 249k92440662 asked May 13 '09 at 8:12 Jakub Šturc 17.9k196996 add a comment| 5 Answers 5 active oldest votes up vote 4 down vote accepted On error resume next: If there is an exception in the program, just ignore it and continue
What Does On Error Goto 0 Do
to the next statement. Considered very bad and ugly, and rightly so in my opinion. It's like having a big: try { // your code } catch { // nothing! muhaha } in every method of your code (or worse, around the whole program). On error goto 0: disables any error handler that is defined in the current procedure. It's like having a big try-catch around your code, which gets disabled as soon as its hit this line. For more information, see the MSDN. share|improve this answer edited May 13 '09 at 8:32 answered May 13 '09 at 8:20 Razzie 19.7k104862 2 +1 Yes. I just discovered this: If you use On Error Goto 0 then every other On Error statement in the procedure becomes disabled. That was totally unexpected. I thought that the documentation was saying that only the last executed error handler is disabled. I expected that if the code reaches another error handler that it would be enabled again but it isn't. –authentictech May 9 '14 at 14:54 add a comment| up vote 4 down vote Have a look here: http://www.powerasp.com/content/new/on-error-resume-next.asp share|improve this answer answered May 13 '09 at 8:20 Seb 411 add a comment| up vote 3 down vote on error go to takes the execution code to a specific code book mark defined in the page.this is useful when you want to perform anything in case an error is
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting
On Error Goto Line
ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the on error exit sub Stack Overflow Community Stack Overflow is a community of 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: asp on error resume next Sign up Why would you ever use “On Error Goto 0”? up vote 19 down vote favorite 5 Why would you ever use "On Error Goto 0" in a VB6 app? This statement turns the error handler off and would mean http://stackoverflow.com/questions/856710/what-does-the-on-error-goto-0-and-error-resume-next-in-old-asp-mean/856740 that any error would crash the app. Why would this ever be desirable? vb6 error-handling share|improve this question asked Apr 2 '12 at 20:37 CJ7 4,99232114220 4 Well, it's certainly a way of implementing fail-fast –Greg Hewgill Apr 2 '12 at 20:39 I don't have VB6 installed, but presumably any Goto statement to a non-existant label would crash the app. –Sam Axe Apr 2 '12 at 20:40 This sounds like a comment from somebody who either throws http://stackoverflow.com/questions/9983464/why-would-you-ever-use-on-error-goto-0 in On Error Resume Next at the head of each procedure and then has mysterious woes that can't be diagnosed, or one who puts in On Error GoTo MyHandler and there just pops up a MsgBox with the same error anyway. –Bob77 Apr 2 '12 at 21:14 2 Not true at all. It is commonly paired with On Error Resume Next and a test of Err.Number to do inline structured error handling. –Bob77 Apr 3 '12 at 0:52 1 @CraigJ: Remember that the error handling is for that procedure (and children) only. "Turning it off" is NOT global, and allows errors to be handled by the parent. –Deanna Apr 3 '12 at 15:28 | show 9 more comments 4 Answers 4 active oldest votes up vote 35 down vote In VB6, you can specify that you want errors to be handled by particular code later in the routine: Sub Bar() On Error Goto MyHandler ... ...some code that throws an error... ... Exit Sub MyHandler: ...some error handler code (maybe pops up a dialog) End Sub It may be the case, however, that the code that throws the error is localized, and you don't want that same handler for all of the rest of the code in the routine. In that case, you'd use "On Error Goto 0" as follows: Sub Bar() ... On Error Goto MyHandler ...some code that throws an error... On Error Goto 0 ... ... Exit Sub MyHandler: ...some er
a tutorial example on how to use 'On Error GoTo 0' to turn off the error handling flag in a procedure to catch the first runtime error. As you can see from the previous http://www.herongyang.com/VBScript/Error-Handling-On-Error-GoTo.html section, my last VBScript example reported the last runtime error, not the first one. https://www.prestwoodboards.com/ASPSuite/KB/Document_View.asp?QID=100411 If you want to catch the first runtime error is a large section of code, you need to: Enter the "On Error Resume Next" statement in the main code to turn on the error handling flag for the main code. Put that section of code into a new subroutine procedure. Enter the "On Error Goto 0" on error statement in the new procedure to turn off the error handling flag for that procedure. Check the Err.Number property right after calling that procedure. Here is the modified VBScript example to catch the first runtime error in a section of code:
Run this modified example code in IE, you will get: There is no error at this time. Before statement: x = 1/0 A runtime error has occurred: Err.Number = 11 Err.Description = Division by zero Err.Source = Microsoft VBScript runtime error What heppened was: When the first runtime error occurred on statement, x = 1/0, in the CodeToBeMonitored() procedure, execution stopped for that procedure, because the error handling flag was turned off for that procedure. Execution control was transferred back to the main code with the runtime error. Back in the main code, the execution continued because
Activity -Unanswered Threads -Most Active Threads -Most Read Threads ASP Classic KB -New & Updated -Most Read -10 Min Quickstarts -Recent Comments Tech Articles ASP Classic News Errors Library File Library Resource Links ASP CLASSICTIDBITS: All as FlashCards Code Snippets FAQs Tips ASP Classic To/From To/FromCODEGuides ASP Classic To/From ASP Classic Study Test PRESTWOODCERTIFIED ASP Classic Study Test ASP Classic Store PRESTWOODSTORE Store Home Buy ASP Classic Items Members Only MEMBERSONLY ASP Classic Member List Member Only KB Posts ASP Classic Content Stats Random Article Random MB Thread Random Tidbit Random CrossRef Code Prestwood eMagazine October Edition Subscribe now! It's Free! Enter your email: ► KB ► Website Scri... ► ASP Classic ► Language Basics Print This From the January2009 Issue of Prestwood eMag ASP Classic Language Basics:Using On Error Resume NextBy Mike Prestwood Posted 10 years ago on 11/15/2006 and updated 7/2/2008 Take Away: You can use "On Error Resume Next" to suppress errors and "On Error Goto 0" to stop suppressing errors. Tags: ASP , On Error Resume Next , trap errors , CDO , send email KB100411 ASP's ability to trap for errors is pretty weak compared to other languages. However, you can trap for errors, suppress errors, and stop suppressing errors. When an error is found, you can also handle it. Suppressing Errors To start trapping errors, add the following line:On Error Resume Next This will suppress all errors for the duration of the script. For example, normally the following code would cause the death of your code with a division by error message:Dim xx = 1/0 However, you can suppress the error as follows:On Error Resume NextDim xx = 1/0 The above code will cause NO error at all. Capture Error But Keep Going While trapping for errors, you can handle the error by inspecting the Err object. The following code snippet handles our division by zero error by displaying a message but the script keeps going:On Error Resume NextDim xx = 1/0If Err.Number <> 0 ThenResponse.Write "Error: " & Err.DescriptionEnd IfResponse.Write "Note, this line here still executes and prints this text." Stop Suppressing Errors After calling On Error Resume Next, you can stop suppressing errors with the following code snippet:On Error Goto 0 Scope of the Err Object The scope of the Err object exists ONLY until you call On Error Goto 0. For example, the following code snippet does NOT display the Err.Description text:On Error Resume NextDim xx = 1/0On Error Goto 0''' Err Object no longer