php - get the first key for an element?

Question

I'm trying to add an extra class tag if an element / value is the first one found in an array. The problem is, I don't really know what the key will be...

A minified example of the array

Array (
    [0] => Array(
            id => 1
            name = Miller
            )
    [1] => Array(
                id => 4
                name = Miller
            )
    [2] => Array(
                id => 2
                name => Smith
    [3] => Array(
                id => 7
                name => Jones
            )
    [4] => Array(
                id => 9
                name => Smith
            )
)

So, if it's the first instance of "name", then I want to add a class.

Answer 1

I think I sort of understand what you're trying to do. You could loop through the array and check each name. Keep the names you've already created a class for in a separate array.

for each element in this array
    if is in array 'done already' then: continue
    else:
        create the new class
        add name to the 'done already' array

Sorry for the pseudo-code, but it explains it fairly well.

Edit: here's the code for it...

$done = array();
foreach ($array as $item) {
    if (in_array($item['name'], $done)) continue;
    // It's the first, do something
    $done[] = $item['name'];
}

Answer 2

I assume you're loop through this array. So, simple condition can be used

$first=0;
foreach ($arr as $value) {
  if (!$first++) echo "first class!";
  echo $value;
  // the rest of process.
}

To get just first value of an array you can also use old fashioned reset() and current() functions

reset($arr);
$first=current($arr);