Ms Excel Vba On Error
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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 when VBA cannot excel vba try catch correctly execute a program statement. We will concern ourselves here only with run time errors. vba error handling best practices Typical run time errors include attempting to access a non-existent worksheet or workbook, or attempting to divide by zero. The example code in this vba error handling in loop 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 time errors do not occur
Vba On Error Exit Sub
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 error handling code and a run time on error goto line 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
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 vba error number and the VBA language provide various tools or means of dealing with errors. Practical Learning:Introducing Error
Vba On Error Goto 0
Handling Open the Georgetown Dry Cleaning Services1 spreadsheet and click the Employees tab Click the Payroll tab Click the TimeSheet tab To
Vba On Error Msgbox
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 http://www.cpearson.com/excel/errorhandling.htm 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 http://www.functionx.com/vbaexcel/Lesson26.htm 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 section. One way you can do this is to add a line marked Exit Sub before the label. This would be done as follows: 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 txtWee
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta http://stackoverflow.com/questions/14158901/difference-between-on-error-goto-0-and-on-error-goto-1-vba 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 us Stack http://www.techrepublic.com/blog/five-apps/five-tips-for-handling-errors-in-vba/ 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, on error helping each other. Join them; it only takes a minute: Sign up Difference between 'on error goto 0' and 'on error goto -1' — VBA up vote 21 down vote favorite 9 Can anyone find the difference between 'On error goto -1' and 'on error goto 0' in VBA? I've tried google and msdn, but I've had vba on error no luck. excel vba msdn share|improve this question asked Jan 4 '13 at 14:22 sterlingalston 155116 This documentation is for Visual Basic, not VBA, but the concepts are similar enough in this case that it should explain the difference. –vcsjones Jan 4 '13 at 14:30 add a comment| 4 Answers 4 active oldest votes up vote 33 down vote accepted On Error GoTo 0 disables any error trapping currently present in the procedure. On Error GoTo -1 clears the error handling and sets it to nothing which allows you to create another error trap. Example: On Error GoTo -1 After the first error is raised, it will GoTo ErrorFound which will then clear the routine's error handling and set a new one, which will GoTo AnotherErrorFound when an error is found. Sub OnErrorGotoMinusOneTest() On Error GoTo ErrorFound Err.Raise Number:=9999, Description:="Forced Error" Exit Sub ErrorFound: On Error GoTo -1 'Clear the current error handling On Error GoTo AnotherErrorFound 'Set a new one Err.Raise Number:=10000, Description:="Another Forced Error" AnotherErrorFound: '
United States Australia United Kingdom Japan Newsletters Forums Resource Library Tech Pro Free Trial Membership Membership My Profile People Subscriptions My stuff Preferences Send a message Log Out TechRepublic Search GO Topics: CXO Cloud Big Data Security Innovation Software Data Centers Networking Startups Tech & Work All Topics Sections: Photos Videos All Writers Newsletters Forums Resource Library Tech Pro Free Trial Editions: US United States Australia United Kingdom Japan Membership Membership My Profile People Subscriptions My stuff Preferences Send a message Log Out Software Five tips for handling errors in VBA Effective error handling can mean the difference between a seamless, user-friendly experience and a problem-plagued application. These best practices will help ensure your apps run as intended, without a hitch. By Susan Harkins | in Five Apps, October 9, 2010, 1:15 AM PST RSS Comments Facebook Linkedin Twitter More Email Print Reddit Delicious Digg Pinterest Stumbleupon Google Plus A professional application always includes adequate error-handling routines to trap unexpected errors. Sometimes, the right handling means the user never knows the error occurred. At the very least, error-handling routines should address the problem, share adequate information on what the user should do next, and exit the program (if absolutely necessary) gracefully. You put a lot of effort into writing the procedures that run your custom applications. Why let a runtime error ruin it all? By employing a few best practices, you can improve error handling. 1: Verify and configure error settings Before you do anything, check the error-trapping settings. VBA, via the Visual Basic Editor (VBE), is flexible and allows you to determine how it responds to errors. To access these settings (shown in Figure A), in the VBE, choose Options from the Tools menu, and click the General tab: Break On All Errors: Stops on every error, even errors following a Resume Next statement. Break On Unhandled Errors: Stops for unhandled errors, but stops on the line calling the class (in class modules) rather than the line with the error, which can be problematic during debugging. Break In Class Modules: Stops at the actual error (line of code), but doesn't work as expected with Err.Raise, which generates an error of its own. Figure A Choose the most appropriate error-handling setting. Well-informed users can change this setting, so I recommend that you include a procedure, similar to the one in Listing A, to your