[Lazarus] Examples of IniPropStorage?

[David W Noon]

On Sat, 2009-02-21 at 19:06 +0100, Luca Olivetti wrote:

> En/na David W Noon ha escrit:
[snip]
> > If there are none, could somebody please give me a quick sample they
> > have knocked up for their own use? Thanks in advance.
>
> Drop a TIniPropStorage on the form, let's call it FormStorage.
> Put all properties you want to preserve in the form SessionProperties 
> (there's a nice dialog to add what you want).
> If you know beforehand the location of the .ini file, just set it in the 
> TIniPropstorage at design time, otherwise assign it in FormCreate.
> Also in FormCreate call restore.
> When you want to save, just call save, e.g.:
> 
> procedure TSettingsForm.FormCreate(Sender: TObject);
> begin
>    FormStorage.IniFileName:=SettingsFilename;
>    FormStorage.Restore;
> end;
> 
> procedure TFormAjustes.SaveButtonClick(Sender: TObject);
> begin
>    FormStorage.Save;
> end;

Thanks for that, Luca. The code is putting me in the right direction.

Now, how do I actually extract key/value pairs from it and store
key/value pairs into it? The only property I have found that looks
likely is the StoredValues collection, but this is too kludgey to be
true, e.g.:

   Name_field.Text := Ini_props.StoredValues['Name'].Value;

That seems to be the sequence required to get a string, and it seems to
segfault if the .INI file is empty. Moreover, the ReadString() method
also segfaults if I use that method instead of the property, e.g.:

   Name_field.Text := Ini_props.ReadString('Name', '<missing>');

The second approach has much neater syntax, plus it allows me to specify
a default value if the required section of the .INI file lacks a value
for that key. But I get access violations when the .INI file is empty.

So, any more tips down at the key/value pair level?

-- 
Regards,

Dave  [RLU #314465]
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david.w.noon at ntlworld.com (David W Noon)
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