Multi-Dimensional Arrays Help - And Other Questions on Arrays

[fjm]

For some reason, I have always had a hard time understanding arrays as they pertain to php and databases. I understand associative arrays just fine but when there are multidimensional arrays, I kinda don't.

I have gone over a few different examples but they were limited. I was able to find one piece of code that I would like to disect and ask questions about so I can gain a better understanding.

$characters = array
(
  array ( name=>"name 1"
  , occupation=>"developer"
  , age=>30
  , specialty=>"Java"
  ),
  array
  (
    name=>"name 2"
    , occupation=>"Programmer"
    , age=>24
    , specialty=>"C++"
  ),
  array
  (
  name=>"name 3"
  , occupation=>"designer"
  , age=>63
  , specialty=>"Javascript"
  )
);
 
foreach ($characters as $val)
{
  foreach ($val as $key=>$final_val)
  {
    print "$key: $final_val<br>";
  }
  print "<br>";
}

In this code, the way I am reading this is that there are 3 "rows"??? or blocks of data. Each one of these rows or blocks has several other rows inside of it. I don't have a problem with the arrays per se but more the foreach loop. If I am incorrect about these 3 arrays being rows, please feel free to correct me.

On the foreach, can someone please tell me exactly how and why it is set up the way it is? Specifically, I don't understand why the coder didn't use a key/value pair. He only uses a value, then inside the loop he uses $key=>$final_val. What I need to understand is why and when to refer to or use the key value pair and when not to. I have also seen code written inside the foreach loop like so: $key['something'] = $val;

What is that? What exactly does it do? If any one can help me to understand these, I would be forever grateful. I have pulled my hair out for the last time on drawing my data out of an array.

Thanks.

[fjm]

lol... Wow.. I never posted so many times in a forum in my life. I think my record was 30 something and that was also on this forum. This one is the record though.

Ok, I am going to try and sleep for a little while. A sincere thanks to both of you guys! I am also putting the both of you on my forum buddy list. :)

[Ciary]

ok cya later fjm and good night/morning :)

[Dormilich]

rest well not dreaming of arrays… they have the possibility to haunt programmer's dreams :)

[fjm]

Thanks a buch guys! I will give my brain a few hours off and then start all over again. :)

Talk to you guys soon.

Frank

[fjm]

Daddy, look! NO HANDS! :P~

$colors = array
(
  array
  (
    'black' => 'sky',
    'blue' => 'ocean',
    'pink' => 'san francisco'
  )
);
 
echo $colors['0']['blue'];
 

For any other poor soul having a hard time with arrays, look at it like this..

            $colors['0']['blue'];
foreach--------^ key-^----^ value

Yields Ocean. ;)

Now kiddies.. when all I need is a single value, instead of using a foreach loop and typing 3 extra lines, I can just type one by using this. ;)

I still may not understand Atli's monster 7D array but I am sure well on my way. Now when I get an undefined index notice, it actually MEANS something to me.

As elementary as arrays may seem to most, I honestly struggled with them but I really feel like I have a much better handle on what is happening and what to do to troubleshoot one and so, I have achieved my goal here thanks to Dormilich, Ciary and Markus.

[Dormilich]

some improvement on the code

$colors[0]['blue'];
        ^--- use integers for numeric arrays

[fjm]

@Dormilich
Thanks Dormilich.. Isn't a 0 an integer?

[Dormilich]

 0  // integer
'0' // string

[fjm]

@Dormilich
Exactly.. That's why I'm a bit confused. I'm not using quotes which should make it an int. No?

[fjm]

Nevermind.... I see it and your right. Thanks Dormi... :)

[Dormilich]

sometimes those type changes can make all the difference in the world (I just got prodded to that yesterday)