Handling Multiple check boxes

[Adrian Parker]

I have a PHP generated page which displays X many records. Each record has
a checkbox preceding it. The user checks several checkboxes, and hits a
delete button. All the corresponding records will be deleted.

But I'm running into difficulty...
Right now the NAME property of each check box is the primary key of the
corresponding record. Hence if I know which checkboxes are checked, I
simply use DELETE using the NAME value.

Generally speaking, how do I get the server side to see which check boxes
were checked?

The check box names may not be sequential, if any records have been deleted
previously, and the first check box might be a number greater than 0.

Is there an easy mechanism to do this? Some kind of built in cnotrol array
allowing me to loop over every check box that was on the form submitted?

I could store the last and first checkbox number in a hidden input, then
loop starting/ending at those values, but that may loop over a lot of
controls that do not exist.
Thoughts?

<Ade
--
Adrian Parker. Ordained priest. <ad***********@ sympatico.ca>

"A society that views graphic violence as entertainment ...should not be
surprised when senseless violence shatters the dreams of it's youngest and
brightest..." - Ensign (March 2004)

[Kelly Thompson]

On Thu, 29 Apr 2004 22:14:59 +0200
Jan Pieter Kunst <de*****@cauce. org> wrote:

In article <Y0************ *******@news20. bellglobal.com> ,
"Adrian Parker" <ad***********@ NOSPAMsympatico .ca> wrote:

Make the "name" attribute an array.

<input type="checkbox" name="checkbox_ id[1]" value="a" />
<input type="checkbox" name="checkbox_ id[3]" value="b" />
<input type="checkbox" name="checkbox_ id[56]" value="c" />
<input type="checkbox" name="checkbox_ id[145]" value="d" />

If a and c are checked, then after submitting
$_REQUEST['checkbox_id'] is an array containing this: [1] => a
[56]=> d.

(Should be [56] => c, sorry)

How can I loop through it without knowing how many elements it
holds?

That's what foreach() is for! See
<http://nl.php.net/manual/en/control-structures.fore ach.php>.

Assuming that the form was submitted with method="post":

foreach($_POST[checkbox_id] as $record_id => $value) {

do_something_in _database($reco rd_id);
...
}

You can also do

reset($array);

while( list($key,$val) = each( $array ) ) {

echo $key . ' => ' . $val;

}

[Adrian Parker]

"Jan Pieter Kunst" <de*****@cauce. org> wrote in message
news:de******** *************** ****@news1.news .xs4all.nl...

In article <qk************ *******@news20. bellglobal.com> ,
"Adrian Parker" <ad***********@ NOSPAMsympatico .ca> wrote:

This seems to work:

foreach(array_k eys($_POST["checkBox_Delet e"]) as $key)
{
if ($deleteCount == 0)
{
$deleteThese = "'" . $key . "'";
$deleteCount += 1;
} else {
$deleteThese .= ", '" . $key . "'";
}
}
This look good to you?

If you need the number of checked checkboxes, it is faster to get that
like this:

$deleteCount = count($_POST['checkBox_Delet e']);

Nah, the deleteCount is just used to see if it's the first element to be
added to the string deleteCount.

deleteCount is building a single quote and comma delimited string that will
be used as argument for a mySQL IN function.

Adrian

[Jan Pieter Kunst]

In article <1C************ *******@news20. bellglobal.com> ,
"Adrian Parker" <ad***********@ NOSPAMsympatico .ca> wrote:

Nah, the deleteCount is just used to see if it's the first element to be
added to the string deleteCount.

deleteCount is building a single quote and comma delimited string that will
be used as argument for a mySQL IN function.

Ah, I see. In that case this will build the querystring in less code:

$querystring = "DELETE FROM ... WHERE ... IN ('" . join("','",
array_keys($_PO ST['checkbox_delet e']) . "')";

JP

--
Sorry, <de*****@cauce. org> is een "spam trap".
E-mail adres is <jpk"at"akamail .com>, waarbij "at" = @.

[Adrian Parker]

"Jan Pieter Kunst" <de*****@cauce. org> wrote in message
news:de******** *************** ****@news1.news .xs4all.nl...

In article <1C************ *******@news20. bellglobal.com> ,
"Adrian Parker" <ad***********@ NOSPAMsympatico .ca> wrote:

Nah, the deleteCount is just used to see if it's the first element to be
added to the string deleteCount.

deleteCount is building a single quote and comma delimited string that will be used as argument for a mySQL IN function.

Ah, I see. In that case this will build the querystring in less code:

$querystring = "DELETE FROM ... WHERE ... IN ('" . join("','",
array_keys($_PO ST['checkbox_delet e']) . "')";

Cool, thanks.
Adrian