in_array is not finding values that are in the array - php

Question

I'm getting strange results when trying to check a $_GET variable against a whitelist array. The variable is in the array but in_array is not finding it. I'll descibe what's happening as best I can.
The $_GET vars are set from option/select choices, three altogether. Only one of the options is giving me a problem. To run a SELECT query, there have to be at least two options chosen. Any combination of the other two options works as expected.
To get the option/select lists I have a SELECT query retrieving a record subset.
From that recordset I use a foreach loop to get the various values to populate the select tags. So the select values are populated by values from the db table. The whitelist arrays are copied from the db.
I check any $_GET vars against the whitelist arrays. The option in question can be a comma-delimited string (eg. 'Italian,Pizza' or 'American, Barbeque, Sandwiches').
To get the select value list for this option I use implode to create a comma-delimited list of each category, then use explode to create an array, then use array_unique to get an array with single instances of each category. When echoing this array everything is right (it populates the select choices correctly).
implode outputs:
Italian,Pizza,Italian,Pizza,Italian,Pizza,Italian,Italian,Sandwiches,Italian,Pizza,Italian
explode outputs:
Array
(
[0] => Italian
[1] => Pizza
[2] => Italian
[3] => Pizza
[4] => Italian
[5] => Pizza
[6] => Italian
[7] => Italian
[8] => Sandwiches
[9] => Italian
[10] => Pizza
[11] => Italian
)
array_unique outputs:
Array
(
[0] => Italian
[1] => Pizza
[8] => Sandwiches
)
So, the URL can be like:
../search.php?var_src=Sandwiches&city_src=Cityname
To sanitize the $_GET vars:
if((isset($_GET['var_src'])) && in_array($_GET['var_src'], $var_array)) {
$var_sort = $_GET['var_src'];
}
Again, $var_array is an array copied from the db table.
This is where the code stops because the $_GET var is not being found in the array.
If I change one of the db records to just one category value (eg. 'Sandwiches') and select that option in the list, then the results are as expected. However, if the record has more than one category value (each of which is in the whitelist array) like 'Pizza,Sandwiches', then neither of them work.
The kicker is that if I include the category value 'Italian', whether alone or with other values in the db record, and select for this value, then it works. I have no idea why.
So the code works if that particular value ('Italian') is selected whether or not others are included as a comma-delimited string for the record, and does not work with other values where there are more than one associated with the record.
I confirmed that the offending value is in the URL and so should work with the code above (in_array($_GET['var_src'], $var_array)).
Also, I don't know why changing the db record would have an effect because the sanitizing against the whitelist happens before selecting records based on the passed values. As far as I can tell, in_array is just not finding legitimate values in the array.
Hope I haven't made this confusing. Thanks for any help.

Answer 1

Not sure if this will help you, try to change it like in this example:
$opt = array( 'Italian,Pizza' , 'American, Barbeque, Sandwiches');
$opts = implode(',',$opt);
$opta = explode(',',$opts);
foreach ($opta as $key=>$value) {
$opta[$key]=trim($value);
}
$opta = array_flip($opta);
var_export($opta);
//now test it simply with isset:
$val = trim($_GET['var_src']);
echo isset($opta[$val])? 'yes':'no';