Re: How do I use Checkboxes and 'Multiple' Select boxes in Web Server applications

Steve Jelfs wrote:
>
> Michael Rothwell wrote:
> >
> > You need to make use of the pl/sql tables and then loop
> > through the table in the procedure that is receiving the
> > information. Always fill the first table element with a
> > dummy value or else if no check boxes are checked you will
> > get an error because no variable was passed. If you look at
> > the BROWSE package that comes with OWS you will find an
> > example of this as used to select which columns of a table
> > to display in a report.
> >
> > Michael.
> >
> > gsimpson_at_liv.ac.uk wrote:
> > >
> > > I am writing some PL/SQL procedures that generate HTML forms that
> > > submit their data to more PL/SQL procedures.
> > > How do I find which checkboxes have been selected in a group? I seem to
> > > be able to get the first one that has been selected, but none of the
> > > others. If I call each checkbox a different name then the procedure only
> > > succeeds if all the boxes are checked.
> > >
> > > A similar problem occurs with select lists in HTML forms. How do I find
> > > which members of the list have been selected?
> > >
> > > Perhaps someone could send me a sample bit of code to handle this.
> > >
> > > Many thanks
> > >
> > > Gawain Simpson
>
> Hmmm......
>
> Well, I do it like this:
> The cursor, c_columns, bring back a number of columns from a table.
> The form then passes the variables to 'pkg.proc' which expects
> v_table VARCHAR2
> data_date DATE
> measure_table_id VARCHAR2
> v_fault_number VARCHAR2
> v_columns owa_util.ident_arr -- The list of columns derived from the
> check boxes.
>
> htp.formOpen(owa_util.get_owa_service_path||'pkg.proc');
> htp.formHidden('data_date',data_date);
> htp.formHidden('v_table', p_table_selected);
> htp.formHidden('measure_table_id',measure_table_id);
> htp.formHidden('v_fault_number',p_fault_number);
> row:=1;
> for crec in c_columns loop
> IF row = 1 THEN
> htp.formCheckBox('v_columns',crec.COL_NM,'CHECKED');
> ELSE
> htp.formCheckBox('v_columns',crec.COL_NM);
> END IF;
> htp.print(crec.COL_NM);
> htp.nl;
> row:= row + 1;
> end loop;
> htp.nl;
> htp.nl;
> htp.formSubmit(NULL, 'Submit');
> htp.hr;
> htp.formClose;
>
> ******************************************
>
> Also, you'll notice that the first check box is checked as default, this
> ensures that the form will always pass at least one value obviating the
> need for a 'dummy' value to be passed
>
> Sj

What if the user unchecks that first box and does not check any others??
You do need the dummy value or you need to write multiple ( overload ) procedures to accept the form data with or without the data.

Michael. Received on Fri Feb 20 1998 - 00:00:00 CET