Error handling

[ecojohnson]

I am new to Visual Basic (one week experience). I have a program that utilizes winsock. The program is the "sender" which sends data to a remote computer. It's incredibly complicated, but works rather well.

However, there is one nagging problem. Our users tend to occasionally get a Run-time error "52" Bad file name or number error. This stops the entire "sending" process, and the user must click [OK] at this message, restart the sender, and everything is back to normal.

It would be nice to somehow trap this error, so that when it occurs, I can automatically restart the sender, rather than forcing the user to. But, the problem is that I can't reproduce this error. More importatnly, I don't know specifically when it occurs. The users who are getting this tend to have a certain type of Novell service pack running on the same machine which I don't have. Therefore, I can't reproduce this error. Plus, it occurs randomly. I doesn't happen at any specific time.

So, my question is this: is there a way that I can trap this error, so that when it occurs, I can write some code to do something, rather than just having a big error jump out on the screen. And, if this is possible, where would I put this error trap in the existing code? Again, I don't know where the error occurs, so I wouldn't have a clue as to where to put this error trap. Is there someplace generic that I can place this so that no matter where/when this error occurs, this error trap can be called?

 

[CajunCenturion]

You might try something like this in the offending routine.

Sub YourRoutine

On Error GoTo HandleError

<you code here>

Exit Sub

HandleError:

if Err = 52 then
<Restart>
Resume
Else
MsgBox &quot;Error: &quot; & Err.Number & &quot;-&quot; & Err.Description
Resume Next
End If

End Sub

And of course you can expand this as your needs arise. Good Luck
--------------
As a circle of light increases so does the circumference of darkness around it. - Albert Einstein

 

[ecojohnson]

Hi CajunCenturion. Thanks for your response.

Do you happen to know an easy way to duplicate a runtime error, so that I can test this to make sure it works?

Also, where would this go in the code? My frmMain has a bunch of subs. Would I place this code just after the Option Explicit statement, or would it go somewhere else (like, within a Form_load subroutine). Does it even matter?

Option Explicit
Private Sub Form_Load()
LoadResStrings Me
Me.Left = GetSetting(App.Title, gstrRegKey, &quot;MainLeft&quot;, 1000)
Me.Top = GetSetting(App.Title, gstrRegKey, &quot;MainTop&quot;, 1000)
Me.Width = GetSetting(App.Title, gstrRegKey, &quot;MainWidth&quot;, 6500)
Me.Height = GetSetting(App.Title, gstrRegKey, &quot;MainHeight&quot;, 6500)
End Sub

Private Sub Form_Unload(Cancel As Integer)
Dim i As Integer

'Stop the Sender
mMain.StopSender
End Sub

Private Sub tmrTimer_Timer()
Dim blnFileIsHere As Boolean

'Check for valid TCP/IP parameters
If gstrRemoteHost = &quot;&quot; Or gintPort = 0 Then
Exit Sub
End If

'Check the state of DataFile object, if both are not closed then don't bother.
'However if there is no send or receive activity for a long time (60 sec.)
' then send the message
If gobjDataFile.State > 0 _
And fMainForm.tcpSender.State > 0 _
And (Date + Time - gdtmTimeOut) * 86400 < gIntConnRetry Then

Exit Sub
End If
End Sub

 

[CajunCenturion]

Add the following line into the offending routine

Err.Raise 52

Be sure to remove it once testing is complete :-D Good Luck
--------------
As a circle of light increases so does the circumference of darkness around it. - Albert Einstein

 

[ecojohnson]

Great. I'll give it a shot. Thanks so much.