Print error to a txt file?

[JamieWarren09]

Hi guys, For some reason when my app is a .exe file it randomly stops responding and crashes every now and then but does not display why. does anyone know how I can make it print the reason why it crashed into a text file?

Thanks
Jamie.

[Zvoni]

Only if you're tracing your code with error-handlers.
Then it's pretty easy to implement an error-log.

If you don't have errorhandlers, then your only option would be the event-log of Windows.

[JamieWarren09]

Thanks, How do I add error-handlers? Basically the team just want to be able to see which errors are causing the app to crash, so we can fix them.

Ta

[Zvoni]

The very basic errorhandler is something like this

Public Sub Something()
 
On Error Goto ErrorHandler
 
'DoSomething
'DoSomethingElse
 
ErrorHandler:
FileNumber = FreeFile
Open "Error.log" For Output As #FileNumber
Print#FileNum, "Error in Function Something: " & Err.Number & " - " & Err.Description
Close#FileNum
'Resume or Exit Sub or blame Microsoft or whatever else
End Sub

[JamieWarren09]

Fantastic, Where would be the best place to put that code? I mean will i have to put it on every public sub to catch an error? or is it possible to have it in one general place?

thanks

[Zvoni]

Fantastic, Where would be the best place to put that code? I mean will i have to put it on every public sub to catch an error? or is it possible to have it in one general place?

thanks

If you pose this question to 5 programmers, you will get 5 different answers

I'm doing it like this:

'In a public Module
Public Sub ErrorHandler(ByRef FunctionName As String, ByVal, ErrNumber As Long, ByRef ErrDescription As String)
Dim FileNumber As Integer
 
FileNumber = FreeFile
Open MyExePath & "\error.log" For Append As #FileNumber
Print#FileNumber, "Date/Time of Error: " & Format(Now,"YYYY.MM.DD HH:MM:SS")
Print#FileNumber, "Error-Code: " & ErrNumber & " - Error-Description: " & ErrDescription
Print#FileNumber, "In Function: " & FunctionName
Close#FileNumber
End Sub

Then in the functions/sub, that contain sensitive code (code which can crash, like saving something to a database, or validating User-Input)

Private Sub MySensitiveCodeSub()
'Dim some Variables here
On Error Resume Next    'DON'T START ON ME ABOUT THIS!
'Execute sensitive Code here
If Err.Number<>0 then   'Err.Number = 0 means: No Error occured
 
    Call ErrorHandler("MySensitiveCodeSub", Err.Number, Err.Description)
    Err.Clear
    'Do something else, like Exit the Sub, give a message to the User, continue with your code, whatever else
    
End If
'Execute other sensitive stuff
 
End Sub

You could even improve my ErrorHandler-Function with a ParamArray Argument to send information about the values of the variables and so on.