[Gambas-devel] Empty string sets controls and collections members to null Question

[richard terry]

On Thursday 27 August 2009 19:55:01 you wrote:

I asked this before (text below) and to my recollection (maybe faulty) Benoit 
said that the behaviour causing me problems was normal, however I really need 
to find a solution.

In a nutshell again it is this:

I use collections to transfer data to-from my database to add/update records 
(don't use the gambas datacontrol).

If an existing collection has a member containing text eg

MyCollection!my_value = "a dog", and I'm updating the record, lets say I've 
deleted the text in the input field, and the value in the backend for that 
field in a table now has to be  an empty sting or null, if I do this:

MyCollectioni!my_value = "", effectively removes the 'my_value' key from the 
collection, dosn't set its string to null.

I would have thought that "" = empty string, not null, but I think Benoit said 
that this was equivalent in gambas. I can't think how to get around this and 
wondered if anyone could think of a solution.

Regards

Richard

> This question is really around how to set a collection member to an empty 
> string without destroying it.
> 
> 
> I've noticed (forever) that this code
> 
> textbox1 = "" when one accidentally forgot to write 
> 
> textbox1.text ="", actually sets the control to null.
> 
> But I've also I just noticed this:
> 
> 
> Lets say you have a collection
> 
> dim aCollection  as new collection
> 
> aCollection!value = "hi there"  
> 
> is a valid statement
> 
> aCollection.Remove("value") -  removes the item
> 
> aCollecton!value = ""  actually works like  aCollection.Remove("value")
> 
> which is sort of inconvenient if you want the collection member to be an
>  empty  string
> 
> Am I wrong ?any suggestions/observations.
> 
> regards
> 
> richard
>