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Re: AfterUpdate Code causes Access failure ("Microsoft Access has stopped working")

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Hi Ron,

Am 12.08.2015 um 15:02 schrieb Ron Paii:
> No, without the nz(..) the comparison will be see if NULL > 0 then ... 
> which will always evaluate to FALSE and don't throw any error, because 
> it is a valid statement! It is only for better reading and a cleaner 
> style, how you want.
>
> Any operation involving Null results in Null.
> ? Null > 0
> outputs
> Null
>
That's it and the if command will interpret it as FALSE.

> The following code
>
> Public Sub TestNull()
>
>    If Null = True Then
>        Debug.Print "Null = True"
>    Else
>        Debug.Print "Null = False"
>    End If
>
>    If Null = False Then
>        Debug.Print "Null = False"
>    Else
>        Debug.Print "Null = True"
>    End If
>
> End Sub
>
> TestNull
> Outputs
> Null = False
> Null = True
>
> I wish VBA would instead raise an error. It would be easer to catch 
> logic errors involving Null.
>
Maybe. I prefer extra handling of the special case that something 
evaluates to null and not to mention the tristate checkboxes!

> ' PS The following changes should make the code more stable
>
> Private Sub CompanyFind_AfterUpdate()
> on error goto errCompanyFind_AfterUpdate
>      Dim rs As Object
> If nz(Me.CompanyFind.Column(3),0) > 0 Then
>     Set rs = Me.Recordset.Clone
>     if rs.recordcount > 0 then ' I like to be paranoid when working on 
> recordsets
>
>          ' Str() indicates [ID] is text, so I added quotes to the search.
>         ' Str() will output a leading space if number is positive.
>         ' Str() will raise an error if you pass it a string that is 
> not a number.
>
>          rs.FindFirst "[ID] =' " & Str(Nz(Me![CompanyFind].Column(3), 
> 0)) & "'"
>          If Not rs.Nomatch Then
>             Me.Bookmark = rs.Bookmark
>      Else:
>          MyCompanySearch
>       endif
>    else
>    MyCompanySearch
> End If
>
> doneCompanyFind_AfterUpdate:
>    on error resume next
>    set rs = nothing ' Never hurts to cleanup after yourself
>    exit sub
>
> errCompanyFind_AfterUpdate:
>    debug.print err.description
>    resume doneCompanyFind_AfterUpdate
> End Sub

I agree with you, an explicit error handling is recommended.

Ulrich

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AfterUpdate Code causes Access failure ("Microsoft Access has stopped working") magmike <magmike7@yahoo.com> - 2015-08-08 23:04 -0700
  Re: AfterUpdate Code causes Access failure ("Microsoft Access has stopped working") Ulrich Möller <knobbi38@arcor.de> - 2015-08-10 13:48 +0200
    Re: AfterUpdate Code causes Access failure ("Microsoft Access has stopped working") "Ron Paii" <None@none.com> - 2015-08-10 07:11 -0500
      Re: AfterUpdate Code causes Access failure ("Microsoft Access has stopped working") Ulrich Möller <knobbi38@arcor.de> - 2015-08-10 14:39 +0200
        Re: AfterUpdate Code causes Access failure ("Microsoft Access has stopped working") "Ron Paii" <None@none.com> - 2015-08-12 08:02 -0500
          Re: AfterUpdate Code causes Access failure ("Microsoft Access has stopped working") Ulrich Möller <knobbi38@arcor.de> - 2015-08-12 18:47 +0200
  Re: AfterUpdate Code causes Access failure ("Microsoft Access has stopped working") magmike <magmike7@yahoo.com> - 2015-08-11 07:54 -0700
  Re: AfterUpdate Code causes Access failure ("Microsoft Access has stopped working") magmike <magmike7@yahoo.com> - 2015-08-11 09:32 -0700
    Re: AfterUpdate Code causes Access failure ("Microsoft Access has stopped working") Ulrich Möller <knobbi38@arcor.de> - 2015-08-12 01:54 +0200
  Re: AfterUpdate Code causes Access failure ("Microsoft Access has stopped working") Patrick Finucane <patrickfinucanetx@gmail.com> - 2015-08-11 12:30 -0700

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