Jump to content

Ghost $_POST in Firefox


heller

Recommended Posts

Hi there! I've got a weird problem with a trivial piece of script... Googled and faqqed my brains off, but still nothing...

There's a table displaying some data from DB. I'm using a drop-down list to set filters for certain columns, e.g.:
[code]
<form name="frmDate" method="post" action="/index.php?section=rep&subsection=ind&dbtFilter=date">
<select name="ddlDate" onchange="document.frmDate.submit()">
<option value="choice=all">all</option>
<option value="min=2006-9-8">previous seven days</option>
<option value="min=2006-9-01">this month</option>
<option value="min=2006-8-01&max=2006-8-31">last month</option>
</select>
</form>
[/code]
As you can see, the name of the field to be filtered is sent by GET (dbtFilter) and the options (choice, min and/or max) are sent by POST.

On receiving the page, I retrieve and save the whole lot in $_SESSION, so that multiple filters can be applied to the table, one by one. Here's the code chunk:
[code]
if (isset($_GET['dbtFilter'])) {

// compose drop-down list name from field name
// and extract filter option pairs (e.g. 'choice=123' or 'max=2006-09-10')
$pairs = explode("&", $_POST['ddl'.ucfirst($_GET['dbtFilter'])]);

// separate option keys and values
foreach ($pairs as $pair) {
$pair = explode("=", $pair);
$options[$pair[0]] = $pair[1];
}

// reset filter for this particular column - new data is here
unset($_SESSION['filters'][$_GET['dbtFilter']]);

// leave the filter empty if 'all' (no filtering) ist set, otherwise save new values
if ($options['choice'] != "all") {
$_SESSION['filters'][$_GET['dbtFilter']] = array(
"choice" => $options['choice'],
"min" => $options['min'],
"max" => $options['max']
);
}
}
[/code]
Thus, if I choose e.g. 'previous seven days' option for the 'Date' column, $_SESSION['filters']['date'] gets filled with data. Next, I choose e.g. 'John Smith' in 'Name', $_SESSION['filters']['name'] gets filled, too. I should have two active filters by now, right?

Now, the problem: in the example above, after I choose 'Smith' (or whatever), previously set $_SESSION['filters']['date']'s three values ('choice', 'min', 'max') get NULLed, all three of them! Moreover, if I click [i]any[/i] link on the page (e.g. sort by some column), any filter's options set with a previous click get NULLed, too. After clicking around I end up with a $_SESSION['filters'][ALL_FILTERABLE_COLUMNS] each filled with three NULL's.

I debugged the whole thing: it works big time until the very end of the script! The $pairs array is initialized, $options too, session dump shows that the data has been saved to a proper place and remained there until the end of the script. It just wouldn't persist until the page has been updated!

After several experiments I discovered there was something wrong with the POST data. If I hard-code any string instead of $_POST['ddl'.ucfirst($_GET['dbtFilter'])], it works, the data doesn't get lost! But I can actually [i]see[/i] the value of $_POST['ddl'.ucfirst($_GET['dbtFilter'])]! It [i]does[/i] go to $_SESSION and activate its very filter on the page.

I tried it on three machines with three different configurations - same result, but what a waste of time: today I found out that in IE everything works perfectly, the multiple filters are there!

Anyone seen this before? Any ideas where I am being had by my favorite FF are very much appreciated.
Link to comment
Share on other sites

I'm interested to see some var_dump()s of your $_GET, $_POST and $_SESSION .. surely there must be something different?

When you say "filled with three NULLs", do you mean that the array $_SESSION['filters'][filter] exists, and each element has value null?  Or does has the array disappeared completely, resulting in any access to its elements returning null?
Link to comment
Share on other sites

[quote author=markbett]read the values from the array and set them to a variable THEN write them back into the array[/quote]
I tried everything: assigning and reassigning to variables, playing with different arrays extracting values with ereg_replace() instead of explode(), splitting strings in different ways etc. While hard-coded strings in any part of the script (e.g. 'blahblah' instead of $pair[1]) remain in $_SESSION forever unless unset or overwritten, but as soon as there [i]anything[/i] derived from $_POST, it vanishes in the thin air.

[quote author=markbett]otherwise ensure you are writing to the correct key value in the array or else you will overwrite the information[/quote]
Even if I messed up with the keys (which I didn't), the information should be overwritten with [i]another[/i] information, not just NULL's.

[quote author=btherl]When you say "filled with three NULLs", do you mean that the array $_SESSION['filters'][filter] exists, and each element has value null?[/quote]
Exactly.

[quote author=btherl]I'm interested to see some var_dump()s of your $_GET, $_POST and $_SESSION .. surely there must be something different?[/quote]
There we go. I'll show only the ['filters'] part of the $_SESSION, and I'll show it twice: before filter adjustment (the script in my original message) and after it. So I load the page with the table:

[tt]$_SESSION['filters']: NULL
$_GET: array(2) { ["section"]=> string(3) "rep" ["subsection"]=> string(3) "ind" }
$_POST: array(0) { }
$_SESSION['filters'] after adjusting: NULL [/tt]

Then I choose 'last month' for the 'Date' column:

[tt]$_SESSION['filters']: NULL
$_GET: array(3) { ["section"]=> string(3) "rep" ["subsection"]=> string(3) "ind" ["dbtFilter"]=> string(4) "date" }
$_POST: array(1) { ["ddlDate"]=> string(27) "min=2006-8-01&max=2006-8-31" }
$_GET['dbtFilter']: string(4) "date"
$_POST['ddl'.ucfirst($_GET['dbtFilter'])]: string(27) "min=2006-8-01&max=2006-8-31"
$pairs: Array ( [0] => min=2006-8-01 [1] => max=2006-8-31 )
$options: Array ( [min] => 2006-8-01 [max] => 2006-8-31 )
$_SESSION['filters'] after adjusting: array(1) { ["date"]=> array(3) { ["choice"]=> NULL ["min"]=> string(9) "2006-8-01" ["max"]=> string(9) "2006-8-31" } }[/tt]

Perfect, isn't it? Everything is seen, found, assigned etc. Okay. Now I go for 'Category' with the ID '1':

[tt]$_SESSION['filters']: array(1) { ["date"]=>  array(3) { ["choice"]=>  NULL ["min"]=>  NULL ["max"]=>  NULL } }
$_GET: array(3) { ["section"]=> string(3) "rep" ["subsection"]=> string(3) "ind" ["dbtFilter"]=> string(8) "category" }
$_POST: array(1) { ["ddlCategory"]=> string(8) "choice=1" }
$_GET['dbtFilter']: string(8) "category"
$_POST['ddl'.ucfirst($_GET['dbtFilter'])]: string(8) "choice=1"
$pairs: array(1) { [0]=> string(8) "choice=1" }
$options: array(1) { ["choice"]=> string(1) "1" }
$_SESSION['filters'] after adjusting: array(2) { ["date"]=> array(3) { ["choice"]=> NULL ["min"]=> NULL ["max"]=> NULL } ["category"]=> array(3) { ["choice"]=> string(1) "1" ["min"]=> NULL ["max"]=> NULL } }[/tt]

Bang! Again, everything is seen and assigned, but the $_SESSION['filters']['date']'s three values (well, two)... Where the shining star are they?

And, again: why are they in place in IE?
Link to comment
Share on other sites

This thread is more than a year old. Please don't revive it unless you have something important to add.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.