comparing two arrays

[Anon]

Is there any way to compare 2 arrays and see if the elements in the first array are present in the second array. This is with respect to drop down boxes.

As in the Array2 is stored in the DB. Andd array1 is availbekl on the page. I am attemptign to creat a drop down box containg all the elements of Array1, but highlighting(selecting) only the the values which are present in ARRAY2.

I know this may seme ab it fuzzy and confusing.. but i need help. I ahve tried all methods am not arriving with the right output. So if you guys can help me with a code or a link..it woudl be nice.

If you odnt understand what i am askign or have any doubts please let me know.

thanks
apoorva

[deckrdx]

You can use something like this when building your dropdown box...

$array2 = get_array_from_db();

print "<select name='mydropdown'>\n";

foreach($array1 as $value) {
print "<option value='$value'>";
if(in_array($value, $array2) {
print "highlight ";
}
print "$value\n";
}

print "</select>\n";

[Anon]

There is a nice little function in the newer version of php4 called array_diff that I tend to use.

http://www.php.net/array-diff

check it out.

Chris King

[toma42]

Good solution. Another way (may be slower than array_diff, I'm not sure) is to serialize the arrays and compare the result with ==