TRUE is not TRUE anymore?

[kewo99]

I went home last Friday with my Access 2003 apps (using ODBC SQL Server backends) working fine (and have functioned for several months). Monday I have issues with all of the True/False fields.
Investigation finds that only -1 is being recognized as True. Previously any non-zero value was recognized as True.

This used to work:
Dim A as Integer
A=1
If A = True Then
<this code would execute before but not now>
End If

This does work:
Dim A As Integer
A=1
If A Then
<this code will still execute now>
End If

Thanks for any enlightenment.

Ken

 

[ProgramError]

Hi Kewo

Just to reasure you, I had a similar problem when I check for a true condition and as your own posting states...

if variable then
<code>
end if

should work, so I suggest, that's the way ahead. I'm not sure if its to do with null values in the data but I was checking for a msgbox reply and comparing for true would not work with it. vbOK did though.

Ian M


Program Error
Why is it, I still think in terms of spectrum BASIC!

 

[RoyVidar]

In Access (and VB, I believe) True = -1 and False = 0, but you'll often find that when testing, 0 evaluates to False, all other numeric values evaluate to True. If you use a bit field in SQL server, I think True = 1 and False = 0.

The comparision "if a = True then" I think would compare whatever value is contained in "a" with -1, which will evaluate to either True or False depedning on "a" being -1 or some other value (all other values than -1 will evaluate to False).

I think the comparision "if a then" will evaluate to True with any numeric value other than 0.

So I think either you have done some changes (i e picking the integer directly from a bit field for test om stead of first assigning it to a boolean, or added the " = True" part) or there's been a logical bomb in the system that hasn't been detected until now.

Roy-Vidar

 

[ZmrAbdulla]

RoyVidar has explained well..
In my experience

Dim A As [b]Boolean[/b]
A=1
If A = True Then
       ' This will work
End If

Dim A As [b]Integar[/b]
A=1
If A = True Then
       ' Never worked
End If

Zameer Abdulla
[sub]Jack of Visual Basic Programming, Master in Dining & Sleeping[/sub]
Visit Me

 

[VBslammer]

When you dimension a variable as Boolean, assigning any non-zero number to the variable will automatically make the variable's value -1. So if you assign A=1 to a boolean variable A, its value will be -1, not 1.

VBSlammer

"You just have to know which screws to turn." - Professor Bob