Retaining Vlaues in Multi-List Boxes

Anon

Here's what I got. A multiple list box in which a user can select multiple items. As long as I submit the form to another page things are fine. The selections will be shown on the resulting page.

However, I want to submit the page to itself and retain the values. I'm guessing it's similar to a defining what is "Selected" in a Drop Down box which is working fine. Everything I've tried with the multi-list box has failed. On the submit, it forgets what was selected.

Anyone have any ideas on how to do this? Is it even possible?

Thanks

majik-sheff

This function will generate all of the <OPTION> tags that go inside of your <SELECT NAME='x' MULTIPLE> Tag:

Just feed this function an array of all of your options and an array of your selected options.

function make_options($options, $selected) {
while (list($key, $val) = each($options)) {
if (array_intersect(array($val), $selected)) {
echo "<OPTION VALUE='$val' SELECTED>$val\n";
} else {
echo "<OPTION VALUE='$val'>$val\n";
}
}
}

Anon

How can you make this working?

<? print(" <center><form action='$PHP_SELF' method='POST'>
<select name='selected'>
<option value='100'>100</option>
<option value='200' selected>200</option>
<option value='300'>300</option>
<option value='400'>400</option>
<option value='500'>500</option>
<option value='600'>600</option>
<option value='700'>700</option>
<option value='800'>800</option>
<option value='900'>900</option>
<option value='1000'>1000</option>
</select><input type='submit' value='Selected Option'>
</form></center>");

$option = array('100','200','300','400','500','600','700','800','900','1000');

// Somethings wrong here I must be tired
make_options($option,$selected);

?>
Can you show us how?Please. Tx.

Majik Sheff wrote:

This function will generate all of the <OPTION> tags that go inside of your <SELECT NAME='x' MULTIPLE> Tag:

Just feed this function an array of all of your options and an array of your selected options.

Anon

This populates the list box and as long as the Form Action submits to another page the values are passed. However, if you submit the page to itself the list box comes back without anything selected.

majik-sheff

$options = array(100, 200, 300, 400, 500, 600, 700, 800, 900, 1000);
echo "<FORM METHOD='POST' ACTION='this_page.php'>" .
"<SELECT NAME='input_name[]' MULTIPLE>"; //notice the [] at the end of input_name
make_options($options, $input_name); //then just feed input_name back into the function
echo "</SELECT></FORM>";

majik-sheff

See my answer under Giovo's post.

Anon

Cool.. It works fine now.. thanks.

Anon

I have a problem with it. I do not undrestand why is this happening? It happend with mine first,... & even with yours. As you can see:

<FORM METHOD='POST' ACTION='this_page.php'><SELECT NAME='input_name[]' MULTIPLE> 
Warning: Argument #2 to array_intersect() is not an array in - on line 13 
<OPTION VALUE='100'>100
 
Warning: Argument #2 to array_intersect() is not an array in - on line 13 
<OPTION VALUE='200'>200
 
Warning: Argument #2 to array_intersect() is not an array in - on line 13 
<OPTION VALUE='300'>300
 
Warning: Argument #2 to array_intersect() is not an array in - on line 13 
<OPTION VALUE='400'>400
 
Warning: Argument #2 to array_intersect() is not an array in - on line 13 
<OPTION VALUE='500'>500
 
Warning: Argument #2 to array_intersect() is not an array in - on line 13 
<OPTION VALUE='600'>600
 
Warning: Argument #2 to array_intersect() is not an array in - on line 13 
<OPTION VALUE='700'>700
 
Warning: Argument #2 to array_intersect() is not an array in - on line 13 
<OPTION VALUE='800'>800
 
Warning: Argument #2 to array_intersect() is not an array in - on line 13 
<OPTION VALUE='900'>900
 
Warning: Argument #2 to array_intersect() is not an array in - on line 13 
<OPTION VALUE='1000'>1000
</SELECT></FORM>

& the line 13 in question is this one here:
if (array_intersect(array($val), $selected)) {

Any idea why? Thanx.

[deleted]

Oh, you've found a bug in my function. Here's the fixed function:

The original function assumed that at least one item would be selected. You were apparently feeding it a case where none were selected.

Anon

Majik I'm affraid that you didn't fix anything,... at least your posts are identical. ;-)

OLD

&&& NEW

Majik you posted the old bugus again. ;-) Yes otherwise it works indeed. Hope you don't mind.

Anon

I tryed to fix it, but I just don't get it.
The only solution for this that I can find, from my limited knowledge is this:

if(!isset($input_name)){
$input_name[] = 100;
}

Is there some other better & more logical?

How do they do those nice things with,...

Yellow 20 Dollars
Blue 30 Dollars
Green 40 Dollars
Red 50 Dollars
Black 70 Dollars

when you select once an option with:

Normal Price 10 Dollrs

Yellow Add 20 Dollars
Blue Add 30 Dollars
Green Add 40 Dollars
Red Add 50 Dollars
Black Add 70 Dollars

& then when you choose another option like red option you get

Yellow Substract 30 Dollars
Blue Substract 20 Dollars
Green Substract 10 Dollars
Red 50 Dollars
Black Add 20 Dollars

How do they do that dinamicly? I really wish to know that?

[deleted]

My apologies, I pasted the wrong code. Here's the right one:

function make_options($options, $selected) {
while (list($key, $val) = each($options)) {
if (is_array($selected) && @array_intersect(array($val), $selected)) {
echo "<OPTION VALUE='$val' SELECTED>$val\n";
} else {
echo "<OPTION VALUE='$val'>$val\n";
}
}
}

Sorry again. 🙂

[deleted]

I think you're talking about changing the form contents when something is clicked? That's done with javascript. Just look at the source of a page that does it.