how to explode html arrays?

[Anon]

I am trying to process an html form, mainly a <select multiple name="class_id[]"> array -

I have the following script to explode the array with a " | " delimiter, but it seems a little longwinded, especially for future forms I will have:

$class = current($class_id);
while ($class) {
echo "$class | ";
$class=next($class_id);
}

This gives me the right output, and if I don't limit the output, it looks as though the array is stored without any delimiter.
I am presuming the one dimensional array I have is stored as (value1, value2, value3...).

If there is a way without using a counter to walk through the array, I'd appreciate it, since it's only going to get ugly when 2 dimensional arrays come in!

[Anon]

for ($i = 0 ; $i < count($class) ; $i++){
echo $class[$i]." | ";
}

[Anon]

Thanks - but I find now when I echo it on the next page, and then submit it to the database, it is no longer an array. MySQL says it's value is "Array", but when I count it it displays 1 (whereas in the echo it was 7). How can I preserve the array from echoing to inserting?

[Anon]

ok, it's late, my eyes are boggled - let me post this and get some zzzz's!

firstly, yes the for loop worked a treat for echoing on the "preview before submitting page".

Now though, I can't get it to submit -

I've tried to put the array into a variable so as to pass it through the subsequent submit button, but no dice :-(

here's what I have which is the page AFTER the multiple selection:

//check the array values
echo ("Array count is ".count($class_id)."<br>");
echo (" \$class_id is: ");
$class=(count($class_id));
for ($i = 0 ; $i < $class ; $i++){
echo $class_id[$i].", ";
$passed_class[]=$class_id[$i];
}

and this outputs:
Array count is 4
$class_id is: 1.6, 2.10, 2.13, 4.22,

so all well and good.

However, on this page, which is a preview page, I have to pass it through another 'submit' button (hence the variable (array?) $passed_class).

I pass it with an <input type=hidden name="passed_class" value="<?=$passed_class?>"

However, the next page has (a similar) script to check the variable:

echo ("Passed array count is ".count($passed_class)."<br>");
echo (" \$passed_class is: ");
$class=(count($passed_class));
for ($i = 0 ; $i < $class ; $i++){
echo $passed_class[$i].", ";
}

However, NOW the output is:
Passed array count is 1
$passed_class is: A,

WTF?!
It's late, maybe I'll see it tomorrow (as usual) but if someone can help would appreciate.

Cheers

[Anon]

How about

echo join($class_id, ' | ');

and to pass it to the next page

foreach ($class_id as $cid) {
echo "<INPUT TYPE=\"HIDDEN\" NAME=class_id[] VALUE=\"$cid\">";
}

this would create a few hidden inputs, each with the same name, preserving the array for the next page

[Anon]

Danny and DotcomTim -

many thanks - I'm still on my learning curve for arrays, but this has been a valuable experience, and both your examples have helped me understand how arrays are handled (sort of!)

I figured out the way of passing Tim's example, and that's to first implode() the array, then explode() later.

Danny's eg is more succinct, and doesn't require processing, so I'll go with that.

Cheers guys - helped me a lot. My staturday is now taken up with fully getting to grips with the function foreach(), which while I'd read up on it, didn't fully understand it's use.

:-)

[Anon]

actually, just one last question -
what is the best way to store an array in mysql? stored as a true array, or an imploded variable, which can be retrieved as an array through explode?
I suppose the former, since it doesn't require the two extra function calls to store/retrieve the data...but just wondering.

[Anon]

I guess if it's just small, and always numbers, you could use a string, but you could also have a table full of array_id's and the values, or if it was a fixed length, just have a table with multiple columns, one for each item

[Anon]

Andy if you like I can send you an example of my form functions that I use for my site.

It will handle multiple arrays with one function call. Sort of the same as Danny's example but you don't have to add or make a new for each different field.

[Anon]

please do -
that would be a huge help
[e-mail]

cheers

[Anon]

Sounds cool, would you mind sending me a copy? It'd be interesting to see how you did it.

[e-mail]