Error Vb6 Example
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Database Guide User login Username: * Password: * Request new password Home › Tutorials Error Handling In Visual Basic Level: Despite your best efforts to cover all possible contingencies, run-time errors will occur in your applications. You can and should do all vb6 try catch example you can to prevent them, but when they happen you have to handle them. Introduction vb6 throw error Trapping Errors at Run-Time Building Error Handlers Raising Your Own Errors Summary Introduction The various functions, statements, properties and methods available in vb6 array example Visual Basic and the components used in Visual Basic expect to deal with certain types of data and behavior in your applications. For example, the CDate() function can convert a value to a Date variable. The function is vb6 ftp example remarkably flexible in the type of information it can accept, but it expects to receive data that it can use to derive a date. If you provide input that it can't convert, it raises error number 13 - "Type mismatch" - essentially saying "I can't handle this input data." In an application, this type of error may be a program logic error (you simply passed the wrong data) or it may be a data entry error
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on the part of the user (you asked for a date and the user typed a name). In the first case, you need to debug the program to fix the mistake. However, there is no way for you to anticipate the behavior of the end users of the application. If the user enters data you can't handle, you need to deal with the situation. Dealing with errors at run-time is a two step process: Trap the Error Before you can deal with an error, you need to know about it. You use VB's On Error statement to setup an error trap. Handle the Error Code in your error handler may correct an error, ignore it, inform the user of the problem, or deal with it in some other way. You can examine the properties of the Err object to determine the nature of the error. Once the error has been dealt with, you use the Resume statement to return control to the regular flow of the code in the application. In addition to dealing with run-time errors, you may at times want to generate them. This is often done in class modules built as components of ActiveX server DLLs or EXEs. It is considered good programming practice to separate the user interface from the program logic as much as possible, so if a server comp
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company Business Learn more about hiring developers or posting ads with us Stack Overflow automation error in vb6 Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 overflow error in vb6 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up what is the better way to handle errors in VB6 up vote 12 down vote favorite 6 I have http://www.vb6.us/tutorials/error-handling VB6 application , I want to put some good error handling finction in it which can tell me what was the error and exact place when it happened , can anyone suggest the good way to do this vb6 error-handling share|improve this question edited Sep 22 '08 at 17:36 Onorio Catenacci 9,01575386 asked Sep 22 '08 at 17:34 RBS 1,30192330 I removed the "in" tag. –Onorio Catenacci Sep 22 '08 at http://stackoverflow.com/questions/116289/what-is-the-better-way-to-handle-errors-in-vb6 17:36 I also changed the two separate "error" and "handling" tags to "error-handling" –Onorio Catenacci Sep 22 '08 at 17:37 add a comment| 7 Answers 7 active oldest votes up vote 2 down vote accepted ON ERROR GOTO and the Err object. See this discussion. share|improve this answer answered Sep 22 '08 at 17:42 Joe Skora 8,97142430 add a comment| up vote 27 down vote First of all, go get MZTools for Visual Basic 6, its free and invaluable. Second add a custom error handler on every function (yes, every function). The error handler we use looks something like this: On Error GoTo {PROCEDURE_NAME}_Error {PROCEDURE_BODY} On Error GoTo 0 Exit {PROCEDURE_TYPE} {PROCEDURE_NAME}_Error: LogError "Error " & Err.Number & " (" & Err.Description & ") in line " & Erl & _ ", in procedure {PROCEDURE_NAME} of {MODULE_TYPE} {MODULE_NAME}" Then create a LogError function that logs the error to disc. Next, before you release code add Line Numbers to every function (this is also built into MZTools). From now on you will know from the Error Logs everything that happens. If possible, also, upload the error logs and actually examine them live from the field. This is about the best you can do for unexpected global error handling in VB6 (one of its many defects
VB6 If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing http://www.vbforums.com/showthread.php?584146-The-best-error-handling-for-VB6 messages, select the forum that you want to visit from the selection below. Results 1 http://www.afralisp.net/archive/vba/error.htm to 18 of 18 Thread: The best error handling for VB6 Tweet Thread Tools Show Printable Version Subscribe to this Thread… Display Linear Mode Switch to Hybrid Mode Switch to Threaded Mode Sep 14th, 2009,02:17 PM #1 vb help View Profile View Forum Posts Thread Starter Lively Member Join Date Apr 2009 Posts 113 The best error handling for VB6 error in Can anyone provide me with a link to the best error handling tutorial out there? Reply With Quote Sep 14th, 2009,02:22 PM #2 techgnome View Profile View Forum Posts PowerPoster Join Date May 2002 Posts 29,804 Re: The best error handling for VB6 fortunately in VB6, there isn't much to it... basically it looks like this: Code: On Error GoTo myErrHandler 'Put the body of the sub/function/what ever here.... :exitClean Exit Sub 'Or Function, what error in vb6 ever :myErrHandler 'Do what you need to do to handle the error here Resum cleanExit End Sub 'function, what ever -tg * I don't respond to private (PM) requests for help. It's not conducive to the general learning of others.* * I also don't respond to friend requests. Save a few bits and don't bother. I'll just end up rejecting anyways.* * How to get EFFECTIVE help: The Hitchhiker's Guide to Getting Help at VBF - Removing eels from your hovercraft * * How to Use Parameters * Create Disconnected ADO Recordset Clones * Set your VB6 ActiveX Compatibility * Get rid of those pesky VB Line Numbers * I swear I saved my data, where'd it run off to??? * Reply With Quote Sep 14th, 2009,02:32 PM #3 vb help View Profile View Forum Posts Thread Starter Lively Member Join Date Apr 2009 Posts 113 Re: The best error handling for VB6 I understand the basics but am looking to create my own error handler so am after something more advanced, thought someone might know where i can find this information to save me reading 100's of tutorials Reply With Quote Sep 14th, 2009,02:37 PM #4 si_the_geek View Profile View Forum Posts Super Moderator Join Date Jul 2002 Location Bristol, UK Posts 38,306 Re: The best error handling for VB6 For some m
in many circumstances. For example, suppose you try to open a text file that the user has deleted. When a compiled program has an error like this, an error message isdisplayed and the program ends. Although you cannot predict and write code for every possible type of error, "File Not Found" errors are fairly easy to handle. If you do not write code towork around the error, you can at least provide a message that makes more sense before ending the program. The "On Error" Statement The most common way to handle error conditions is to use Visual Basic's"On Error" statement.The "On Error" statement interrupts the normal flow of your program when an error occurs and begins executing your error handling code. A typical use is as follows :
On Error Goto FileOpenError When this statement is executed, any errors that occur in subsequentstatements cause Visual Basic to stop normal line-by-line execution andjump to the statement labeled as "FileOpenError". Labeling Code Lines Line labels in Visual Basic are similar to the line numbers of early BASIC.In Visual Basic, line labels can include text if you want, but each label mustbe unique. They are followed by a colon (:), as in the following example : Private Sub Form_Load () On Error Goto FileOpenError Open "C:\SOMEFILE.TXT" For Unput As #1 Line Input #1, sData Exit Sub FileOpenError: MsgBox "There was a problem opening the file. Stop for coffee!" End End Sub In the preceding sample code, if the "Open" or "Line Input" statements causean error, the statements starting at the label "FileOpenError" are executed,causing the message to be displayed and ending the program. You should note a few points about the sample code. First, note the locationand style of the error handling routine. It is usually placed near the end of thesubroutine, with the label not indented to indicate a special section of code. Second, and more important, note the "Exit Sub" statement after the "Open" statement. It is necessary to prevent the error handler routine from executingeven when the "Open" statement was successful. Controlling Program Flow After an Error In the preceding code example, you simply end the program if an error occurs. However, you can handle the error in several (better) ways : Exit the subroutine after informing the user of the error, and allow the program to continue running with limited functionality. Resume execution with the next statement following the error. Provide a way for the user to correct the error and retry the offending statement. You can also have multiple labels within a procedure and set the current error handler multiple times. For example, you can add a line to the code