Forum: Ruby Init attributes and set value

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00197f7c716dba70bbe3dd1c68ba4404?d=identicon&s=25 Stephan Meier (pure)
on 2008-10-26 16:54
Hey all,

sorry for the noob question.

But how can i init a big amount of attributes with empty strings.
And overwrite the empty string if the field of the form is filled with
some value.

I try update_attributes(hash) with no success.

Thanks for your help! :)
E0d864d9677f3c1482a20152b7cac0e2?d=identicon&s=25 Robert Klemme (Guest)
on 2008-10-26 17:10
(Received via mailing list)
On 26.10.2008 16:54, Stephan Meier wrote:

> But how can i init a big amount of attributes with empty strings.

I'd use nil as the marker for uninitialized.  This happens to be the
default and saves the overhead of all the empty strings.  You can deal
with those nils later, i.e. when changing or outputting them, e.g.

def modify_whatever(s)
   (@whatever ||= "") << s
end

def print_whatever
   print @whatever || ""
end

You can even automate this by writing your own attr_accessor method that
will define getters like

def foo
   @foo || ""
end

> And overwrite the empty string if the field of the form is filled with
> some value.

Form, what form?

> I try update_attributes(hash) with no success.

Can you be more specific about what you are really trying to do?  Is
this web, UI or what?

Kind regards

  robert
00197f7c716dba70bbe3dd1c68ba4404?d=identicon&s=25 Stephan Meier (pure)
on 2008-10-26 17:16
Hey,

thanks for your answer.

I have a form (html rails form) and want to generate a search url with
every textfield.

The URL looks like http://example.com?value1=&value2=&value3=& ....

The url has about 20 values but its not necessary every value has to be
filled.
So i want to update only these values from my "search form" wich have a
value and the rest with an empty string. :)

thanks for your help :)
D337e2cf7c6d03caac6988d83e0e7f66?d=identicon&s=25 Michael Guterl (mguterl)
on 2008-10-26 17:31
(Received via mailing list)
On Sun, Oct 26, 2008 at 12:16 PM, Stephan Meier <phoenix@oleco.net>
wrote:
> filled.
> So i want to update only these values from my "search form" wich have a
> value and the rest with an empty string. :)
>
> thanks for your help :)

I'm sure Robert helped answer your question and I know this isn't the
Rails list, but this will hopefully help even further.

http://railscasts.com/episodes/111

HTH,
Michael Guterl
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