On Error Goto 0 In Vb
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On Error Goto Line
a community of 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Why would you ever use
On Error Exit Sub
“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 that any error would crash the app. Why would
On Error Goto 0 In Qtp
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 in On Error Resume Next at the head of each procedure and then has mysterious on error goto 1 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 error handler code (maybe pops up a dialog) End Sub Now you have effectively scoped the error handling to execute only if that particular line of code fails. By calling
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 ads with try catch vba us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow vba on error resume next turn off Community Stack Overflow is a community of 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up What err.number vba 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 sure about semantics of on error goto 0 and error resume http://stackoverflow.com/questions/9983464/why-would-you-ever-use-on-error-goto-0 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 to the next statement. Considered very bad and ugly, and rightly so in my opinion. It's http://stackoverflow.com/questions/856710/what-does-the-on-error-goto-0-and-error-resume-next-in-old-asp-mean 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 encountered. On error resume next moves on to the next code of execution after the erroneous code. Basically ignores the error and continues with the code. This is particulary useful when you
a tutorial example on how to use 'On Error GoTo 0' to turn off the error handling flag http://www.herongyang.com/VBScript/Error-Handling-On-Error-GoTo.html in a procedure to catch the first runtime error. As you can see from the previous section, my last VBScript example reported the last runtime error, not the first one. If you want to catch the first runtime error is a large section of code, you need to: Enter the "On Error Resume Next" on error 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" statement in the new procedure to turn off the error handling flag for that procedure. Check the Err.Number property right after calling that on error goto procedure. Here is the modified VBScript example to catch the first runtime error in a section of code: