How to use a foreach loop, but do something different on the last iteration?

Question

This is probably a simple question, but how do you iterate through an array, doing something to each one, until the last one and do something different?

I have an array of names. I want to output the list of names separated by commas.

Joe, Bob, Foobar

I don't want a comma at the end of the last name in the array, nor if there is only one value in the array (or none!).

Update: I can't use implode() because I have an array of User model objects where I get the name from each object.

$users = array();
$users[] = new User();

foreach ($users as $user) {
    echo $user->name;
    echo ', ';
}

How can I achieve this and still use these objects?

Update: I was worrying too much about how many lines of code I was putting in my view script, so I decided to create a view helper instead. Here's what I ended up with:

$array = array();
foreach($users as $user) {
    $array[] = $user->name;
}
$names = implode(', ', $array);

Answer 1

Use implode:

$names = array('Joe', 'Bob', 'Foobar');
echo implode(', ', $names); # prints: Joe, Bob, Foobar

To clarify, if there is only one object in the array, the ', ' separator will not be used at all, and a string containing the single item would be returned.

EDIT: If you have an array of objects, and you wanted to do it in a way other than a for loop with tests, you could do this:

function get_name($u){ return $u->name; };
echo implode(', ', array_map('get_name', $users) ); # prints: Joe, Bob, Foobar

Answer 2

$array = array('joe', 'bob', 'Foobar');
$comma_separated = join(",", $array);

output:

joe,bob,Foobar

Answer 3

Sometimes you might not want to use implode. The trick then is to use an auxiliary variable to monitor not the last, but the first time through the loop. vis:

$names = array('Joe', 'Bob', 'Foobar');
$first = true;
$result = '';
foreach ($names as $name)
{
   if (!$first)
      $result .= ', ';
   else
      $first = false;

   $result .= $name;
}