submit empty checkboxes to db

[witold]

Hi,

I have a number of rows with checkboxes:

echo '<tr><td class="text">'.$rowProduct['product'].'</td><td class="text"><input name="price[]" type="text" value="'.$rowProduct['price'].'" class="text"><input name="id[]" type="hidden" value="'.$rowProduct['ID'].'"></td><td width=50><input name="available[]" type="checkbox" value="1"></td></tr>';

if I check some of checkboxes and click submit, data should be submitted to DB:

if ($HTTP_POST_VARS){
for ($i =0; $i<count($price); $i++) {
if (!isset($available[$i])) $available[$i] = 0; //if empty
$connector->query('UPDATE test SET price="'.$price[$i].'",available='.$available[$i].' WHERE ID='.$id[$i]);
}
}

Text values (prices) are submitted correctly, however, checkboxes aren't. If I check 2 random checkboxes they are written in DB as the first 2. On the other hand, If I uncheck any 3-4 checkboxes and leave others checked, only the last 3-4 checkboxes are set to 0 in DB.

I've tried to check before submission if a checkbox is empty:
if (!isset($available[$i])) $available[$i] = 0; //if empty
but it doesn't work.

Any idea?

witold

[jansky]

here change to
<input type="checkbox" name="available[]" value="'.$rowProduct['ID'].'">

and when submitted
$available=$_POST['available'];
for ($x=0;$x<count($available0;$x++)
{
mysql_query("update yourtable set available=1 where id=$available[$x]");
}

[witold]

Sorry, but it doesn't work. I did it the way you wrote. Yet, no checkboxes get updated to DB 🙁

[mrhappiness]

Unchecked checkboxes are not transmitted so you need some serv sided logic to determine which checkboxes you displayed in the form just having been submitted

[witold]

exactly. if i have a set of 4 checkboxes (all have DB value = 1) and uncheck 2 of them in order to set their db value to 0, nothing happens, because the above script updated the value of checked items only.

i've been struggling with a script to determine which checkboxes have been checked. i understand this needs to be done with array of product ids. then, weed out ids corresponding to ids of checkboxes. the rest are ids that should be updated in db...

am i correct?

[Roger_Ramjet]

Yes.

Personal solution would be a javascript function in the page head that added the UNCHECKED id to an array in a hidden field on the form. Would make processing the submitted data much easier.

If you don't know/like js then yes, you have to match products and checkboxes.

Put the row product ids into an array and do an array match against the available[] array with array_diff . This will give you all the row ids not in the available array.

[witold]

OK. I've got it.
I only wonder, if this could be done using a cleaner code?

if ($HTTP_POST_VARS){ 

//First I assign names to arrays containing posted data

$array1 = $_POST['id'];
$array2 = $_POST['available'];

//Since $available[] contains product ids submitted via post
//and unchecked checkboxes don't carry any ids, 
//I want compare 2 arrays and find missing ids

$diff = array_diff($array1, $array2); 

//Now I update all prices and set all available to 1
//including those unchecked

for ($i =0; $i<count($_POST['price']); $i++) { 
$connector->query('UPDATE test SET price="'.$_POST['price'][$i].'",available=1 WHERE ID='.$_POST['id'][$i]);
}

//Finally, I set unchecked available to 0

foreach($diff as $variable => $value){ 
$connector->query('UPDATE test SET available=0 WHERE ID='.$diff[$variable]);   

 } 

 }

I know this isn't perfect, so maybe someone could tell me how to merge both loops?

[Roger_Ramjet]

Dunno about merging the 2 loops, bit beyond me that. :queasy:

I do know how to change the second loop into 1 query though :p

$str = implode(',' , $diff);

$sql = "UPDATE test SET available=0 WHERE id IN (". $str .")";

I'm sure I could do the same with the first loop if I thought about it a bit - probably requires changing the html form to suit 😃