On Error Goto Errorhandler Vba Excel
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three flavors: compiler errors such as undeclared variables that prevent your code from compiling; user data entry error such as a user entering a negative value where only a positive number is acceptable; and run time errors, that occur excel vba try catch when VBA cannot correctly execute a program statement. We will concern ourselves here only with
On Error Goto Vba
run time errors. Typical run time errors include attempting to access a non-existent worksheet or workbook, or attempting to divide by zero. The
Vba Error Handling In Loop
example code in this article will use the division by zero error (Error 11) when we want to deliberately raise an error. Your application should make as many checks as possible during initialization to ensure that run
Vba Error Handling Best Practices
time errors do not occur later. In Excel, this includes ensuring that required workbooks and worksheets are present and that required names are defined. The more checking you do before the real work of your application begins, the more stable your application will be. It is far better to detect potential error situations when your application starts up before data is change than to wait until later to encounter an error situation. If you have no on error goto line error handling code and a run time error occurs, VBA will display its standard run time error dialog box. While this may be acceptable, even desirable, in a development environment, it is not acceptable to the end user in a production environment. The goal of well designed error handling code is to anticipate potential errors, and correct them at run time or to terminate code execution in a controlled, graceful method. Your goal should be to prevent unhandled errors from arising. A note on terminology: Throughout this article, the term procedure should be taken to mean a Sub, Function, or Property procedure, and the term exit statement should be taken to mean Exit Sub, Exit Function, or Exit Property. The term end statement should be taken to mean End Sub , End Function, End Property, or just End. The On Error Statement The heart of error handling in VBA is the On Error statement. This statement instructs VBA what to do when an run time error is encountered. The On Error statement takes three forms. On Error Goto 0 On Error Resume Next On Error Goto
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 vba on error exit sub with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack vba on error goto 0 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: Sign vba error number up Excel VBA: On Error Goto statement not working inside For-Loop up vote 7 down vote favorite 1 I'm trying to cycle through a table in excel. The first three columns of this table have text headings, the rest of them have http://www.cpearson.com/excel/errorhandling.htm dates as headings. I want to assign those dates, sequentially, to a Date-type variable, and then perform some operations based on the date To do this I am using a foreach loop on myTable.ListColumns. Since the first three columns do not have date headers, I have tried to set the loop up so that, if there is an error assigning the header string to the date-type variable, the loop goes straight to the next column This seems to work for the first column. http://stackoverflow.com/questions/11998836/excel-vba-on-error-goto-statement-not-working-inside-for-loop However, when the second column's header is 'assigned' to the date-type variable, the macro encounters an error even though it is within an error-handling block Dim myCol As ListColumn For Each myCol In myTable.ListColumns On Error GoTo NextCol Dim myDate As Date myDate = CDate(myCol.Name) On Error GoTo 0 'MORE CODE HERE NextCol: On Error GoTo 0 Next myCol To reiterate, the error is thrown on the second round of the loop, at the statement myDate = CDate(myCol.Name) Can anyone explain why the On Error statement stops working? excel vba excel-vba for-loop error-handling share|improve this question asked Aug 17 '12 at 1:52 Swiftslide 41751828 Rather than using an error as your control structure, maybe an IF with an IsDate function would be more suitable in this scenario? –ray Aug 17 '12 at 2:29 1 If you are "blindly" handling the error - rather than taking specific action on an error type - then you should just use an On Error Resume Next outside your loop. At the moment you are using error handling afresh on each column. –brettdj Aug 17 '12 at 2:40 1 @brettdj, I don't think you can just resume next. The whole idea is to skip over the "more code here" code if the date conversion fails. So you need to go into a handler so that you can resume to a specific line. In addition, you only want the handler enabled for the date conversion, not the entire loop body. –paxdiabl
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings http://stackoverflow.com/questions/19042604/vba-excel-error-handling-especially-in-functions-professional-excel-developm and policies of this site About Us Learn more about Stack Overflow http://www.functionx.com/vbaexcel/Lesson26.htm the company Business Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question 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; it on error only takes a minute: Sign up VBA Excel Error Handling - especially in functions - Professional Excel Development Style up vote 5 down vote favorite 4 I got the book "Professional Excel Development" by Rob Bovey and it is opening up my eyes. I am refitting my code with error handling. However, there is a lot I don't understand. I on error goto especially need to know how to correctly use it in functions. I use Bovey's rethrow version of the error handler (at bottom). When I started, I was using the basic boolean (non-rethrow) method and turned my subroutines into boolean functions. (P.S. I am switching back to the boolean method based on the answer.) I need guidance on how to fit functions into this scheme. I want them to return their real values (a string or double, e.g., or -1 if they fail in some cases) so I can nest them in other functions and not just return an error handling boolean. This is what a typical subroutine call to bDrawCellBorders(myWS) would look like within an entry point. Sub calls seem to be working well. (I.e. it is a subroutine that was turned into a function only so it can return a boolean to the error handling scheme.) Sub UpdateMe() ' Entry Point Const sSOURCE As String = "UpdateMe()" On Error GoTo ErrorHandler Set myWS = ActiveCell.Worksheet Set myRange = ActiveCell myWS.Unprotect ' lots of code If Not bDrawCellBorder
the wrong time. The application may crash. A calculation may produce unexpected results, etc. You can predict some of these effects and take appropriate actions. Some other problems are not under your control. Fortunately, both Microsoft Excel and the VBA language provide various tools or means of dealing with errors. Practical Learning:Introducing Error Handling Open the Georgetown Dry Cleaning Services1 spreadsheet and click the Employees tab Click the Payroll tab Click the TimeSheet tab To save the workbook and prepare it for code, press F12 Specify the folder as (My) Documents In the Save As Type combo box, select Excel Macro-Enabled Workbook Click Save Introduction to Handling Errors To deal with errors in your code, the Visual Basic language provides various techniques. One way you can do this is to prepare your code for errors. When an error occurs, you would present a message to the user to make him/her aware of the issue (the error). To prepare a message, you create a section of code in the procedure where the error would occur. To start that section, you create a label. Here is an example: Private Sub cmdCalculate_Click() ThereWasBadCalculation: End Sub After (under) the label, you can specify your message. Most of the time, you formulate the message using a message box. Here is an example: Private Sub cmdCalculate_Click() ThereWasBadCalculation: MsgBox "There was a problem when performing the calculation" End Sub If you simply create a label and its message like this, its section would always execute: Private Sub cmdCalculate_Click() Dim HourlySalary As Double, WeeklyTime As Double Dim WeeklySalary As Double ' One of these two lines could produce an error, such as ' if the user types an invalid number HourlySalary = CDbl(txtHourlySalary) WeeklyTime = CDbl(txtWeeklyTime) ' If there was an error, the flow would jump to the label WeeklySalary = HourlySalary * WeeklyTime txtWeeklySalary = FormatNumber(WeeklySalary) ThereWasBadCalculation: MsgBox "There was a problem when performing the calculation" End Sub To avoid this, you should find a way to interrupt the flow of the program before the label sect