Arrays - Practical PHP Programming

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So far we've looked at the basic variables types such as strings and integers, as well as a variety of functions you can use to manipulate these data types. Beyond the basic data types are arrays and objects, which take a little bit more work in order for you to take advantage of them properly. More importantly, arrays take a solid understanding of functions before you try to use them, which is why they are separated here! As mentioned, objects are covered exclusively in their own chapter - this chapter is dedicated to the topic of arrays.

In order to model our surroundings in a programming environment accurately, it is important to recognise that some types of data naturally group together - colours, for example, naturally clump together into one group. Rather than having hundreds of separate variables - one for each colour - the reality is that it makes more sense to have one variable that holds a list, or array of colours.

Topics covered in this chapter are:

Reading arrays

Manipulating arrays

Multidimensional arrays (arrays of arrays)

Saving arrays

Chapter contents

GamingG@firefoxowns.com - 04 Jul 2008

I believe Gayatri was writing the array in PHP syntax, but intended for the information to be retrieved from the database. I was just working on something similar, so here's my code, in case it helps:

$forumq = $g_mysql->query("SELECT * FROM `forums` WHERE `is_category`=0 ORDER BY `forder`");

$allforuma = array();
while($a = $g_mysql->fetch_array($forumq))
{
if(!array_key_exists($a['parent_id'], $allforuma))
{
$allforuma[$a['parent_id']] = array();
}

$allforuma[$a['parent_id']][] = $a;
}