Goto Error
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resources Windows Server 2012 resources Programs MSDN subscriptions Overview Benefits Administrators Students Microsoft Imagine Microsoft Student Partners ISV Startups TechRewards Events Community Magazine Forums Blogs Channel 9 Documentation APIs and reference Dev centers Retired content Samples We’re sorry. The content on error goto line you requested has been removed. You’ll be auto redirected in 1 second. Language Reference on error goto 0 Statements I-P I-P On Error Statement On Error Statement On Error Statement If...Then...Else Statement Implements Statement Input # Statement Kill Statement
On Error Resume Next Vbscript
Let Statement Line Input # Statement Load Statement Lock, Unlock Statements LSet Statement Mid Statement MkDir Statement Name Statement On Error Statement On...GoSub, On...GoTo Statements Open Statement Option Base Statement Option Compare Statement Option Explicit
On Error Exit Sub
Statement Option Private Statement Print # Statement Private Statement Property Get Statement Property Let Statement Property Set Statement Public Statement Put Statement TOC Collapse the table of content Expand the table of content This documentation is archived and is not being maintained. This documentation is archived and is not being maintained. Visual Basic for Applications Reference Visual Studio 6.0 On Error Statement See Also Example Specifics Enables an error-handling routine and on error goto vbscript specifies the location of the routine within a procedure; can also be used to disable an error-handling routine. Syntax On Error GoTo line On Error Resume Next On Error GoTo 0 The On Error statement syntax can have any of the following forms: Statement Description On Error GoTo line Enables the error-handling routine that starts at line specified in the required line argument. The line argument is any line label or line number. If a run-time error occurs, control branches to line, making the error handler active. The specified line must be in the same procedure as the On Error statement; otherwise, a compile-time error occurs. On Error Resume Next Specifies that when a run-time error occurs, control goes to the statement immediately following the statement where the error occurred where execution continues. Use this form rather than On Error GoTo when accessing objects. On Error GoTo 0 Disables any enabled error handler in the current procedure. Remarks If you don't use an On Error statement, any run-time error that occurs is fatal; that is, an error message is displayed and execution stops. An "enabled" error handler is one that is turned on by an On Error statement; an "active" error handler is an enabled handler that is in the pro
crystal-clear structure, without giving much thought to the often ugly topic of error handling. But unfortunately in programming, perhaps more than in any other kind of engineering, the devil is in the details. The handling of errors and of
On Error Resume Next In Qtp
irregular inputs and data usually requires more code than the straight-line algorithm for solving the vba on error goto 0 problem itself. This is a regrettable but unavoidable artifact of our craft. But wait, there's more. As difficult as error handling is, coupled with vba error handling best practices resource allocation and the need for robust deallocation it is nothing short of a huge headache. Fortunately, in newer high-level languages this is less of a problem because of automatic garbage collection. Also, C++ provides tolerably robust solutions in the https://msdn.microsoft.com/en-us/library/aa266173(v=vs.60).aspx form of RAII. But as the title states, here I'm concerned with C, which doesn't have exceptions and destructors, so the issue is much more difficult. In this article I will argue that the much hated goto statement is a valuable tool for simplifying error-handling code in C. A simple case Here's a quote from the Wikipedia article on RAII: C requires significant administrative code since it doesn't support exceptions, try-finally blocks, or RAII at all. A typical approach is http://eli.thegreenplace.net/2009/04/27/using-goto-for-error-handling-in-c to separate releasing of resources at the end of the function and jump there with gotos in the case of error. This way the cleanup code need not be duplicated. The code sample the article shows is this: int c_example() { int ret = 0; // return value 0 is success FILE *f = fopen("logfile.txt", "w+"); if (!f) return -1; if (fputs("hello logfile!", f) == EOF) { ret = -2; goto out; } // continue using the file resource // ... // Releasing resources (in reverse order) out: if (fclose(f) == EOF) ret = -3; return ret; } Sure, by inverting the logical comparison, this can be rewritten without a goto as follows: int c_example() { int ret = 0; // return value 0 is success FILE *f = fopen("logfile.txt", "w+"); if (!f) return -1; if (fputs("hello logfile!", f) != EOF) { // continue using the file resource } else { ret = -2; } if (fclose(f) == EOF) ret = -3; return ret; } Although we've gotten rid of the goto, IMHO this code isn't much cleaner. Note that we've just moved the mainline code into a condition. Will we do it for any error condition the function encounters? A thornier case Now consider this snippet: int foo(int bar) { int return_value = 0; allocate_resources_1(); if (!do_something(bar)) goto error_1; allocate_resources_2(); if (!init_stuff(bar)) goto error_2; allocate_resources_3(); if (!prepare_stuff(bar)) goto error_3; return_value = do_the_thing(bar); error_3: cleanup_3(); error_2: cleanup_
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 http://programmers.stackexchange.com/questions/154974/is-this-a-decent-use-case-for-goto-in-c ads with us Programmers Questions Tags Users Badges Unanswered Ask Question _ Programmers Stack Exchange is a question and answer site for professional programmers interested in conceptual questions about software development. Join them; it only takes a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top Is this a decent use-case for goto in C? up vote 38 down vote favorite 9 I on error really hesitate to ask this, because I don't want to "solicit debate, arguments, polling, or extended discussion" but I'm new to C and want to gain more insight into common patterns used in the language. I recently heard some distaste for the goto command, but I've also recently found a decent use-case for it. Code like this: error = function_that_could_fail_1(); if (!error) { error = function_that_could_fail_2(); if (!error) { error = function_that_could_fail_3(); ...to the n-th tab level! } else { // on error goto deal with error, clean up, and return error code } } else { // deal with error, clean up, and return error code } If the clean-up part is all very similar, could be written a little prettier (my opinion?) like this: error = function_that_could_fail_1(); if(error) { goto cleanup; } error = function_that_could_fail_2(); if(error) { goto cleanup; } error = function_that_could_fail_3(); if(error) { goto cleanup; } ... cleanup: // deal with error if it exists, clean up // return error code Is this a common or acceptable use-case of goto in C? Is there a different/better way to do this? c design-patterns goto share|improve this question edited Jun 30 '12 at 13:21 Bill the Lizard 7,50683386 asked Jun 30 '12 at 1:49 Robz 9213910 2 See also this question (and my answer). –Keith Thompson Jun 30 '12 at 3:32 1 That's probably the one excuse for goto, of course if you really object you can use c++ and exceptions - but that's just goto with a sugar coating –Martin Beckett Jun 30 '12 at 3:37 1 @DeadMG You'd still end up with lots of nesting. –Izkata Jun 30 '12 at 3:40 4 @DeadMG: Using another language is not always an option. –Benjamin Kloster Jun 30 '12 at 11:38 10 I think with appropriate label naming, example may look quite decent: goto hell; –gnat Jun 30 '12 at 11:50 | show 8 more comments 12 Answers