How do I create a comma-separated list from an array in PHP?

Question

I know how to loop through items of an array using foreach and append a comma, but it's always a pain having to take off the final comma. Is there an easy PHP way of doing it?

$fruit = array('apple', 'banana', 'pear', 'grape');

Ultimately I want

$result = "apple, banana, pear, grape"

Equites

Answer 1

You want to use implode for this.

ie: $commaList = implode(', ', $fruit);

---

There is a way to append commas without having a trailing one. You'd want to do this if you have to do some other manipulation at the same time. For example, maybe you want to quote each fruit and then separate them all by commas:

$prefix = $fruitList = '';
foreach ($fruits as $fruit)
{
    $fruitList .= $prefix . '"' . $fruit . '"';
    $prefix = ', ';
}

Also, if you just do it the "normal" way of appending a comma after each item (like it sounds you were doing before), and you need to trim the last one off, just do $list = rtrim($list, ', '). I see a lot of people unnecessarily mucking around with substr in this situation.

Norford

It would make more sense (if trying to add quotes) to call <code>$fruitlist = '"' . implode( '", "', $fruit) . '"';</code> – Cortes

The foreach loop is better if you want to manipulate that data in the array before making it into a string; For example, addslashes, or mysql_real_escape_string. – Spurtle

Edge case: a string that contains both single and double-quotes - how to adjust for that? – Sublieutenant

Answer 2

This is how I've been doing it:

$arr = array(1,2,3,4,5,6,7,8,9);

$string = rtrim(implode(',', $arr), ',');

echo $string;

Output:

1,2,3,4,5,6,7,8,9

Live Demo: http://ideone.com/EWK1XR

EDIT: Per @joseantgv's comment, you should be able to remove rtrim() from the above example. I.e:

$string = implode(',', $arr);

Hebrides

As answered above, you could just do implode(',', $arr) – Among

@Among You're right, I don't know why I use rtrim(). I recall having a problem with there being extra commas on the end of the string, but can't remember the situation where it was happening. – Hebrides

Answer 3

Result with and in the end:

$titleString = array('apple', 'banana', 'pear', 'grape');
$totalTitles = count($titleString);
if ($totalTitles>1) {
    $titleString = implode(', ', array_slice($titleString, 0, $totalTitles-1)) . ' and ' . end($titleString);
} else {
    $titleString = implode(', ', $titleString);
}

echo $titleString; // apple, banana, pear and grape

Summer

Answer 4

Similar to Lloyd's answer, but works with any size array.

$missing = array();
$missing[] = 'name';
$missing[] = 'zipcode';
$missing[] = 'phone';

if( is_array($missing) && count($missing) > 0 )
        {
            $result = '';
            $total = count($missing) - 1;
            for($i = 0; $i <= $total; $i++)
            { 
              if($i == $total && $total > 0)
                   $result .= "and ";

              $result .= $missing[$i];

              if($i < $total)
                $result .= ", ";
            }

            echo 'You need to provide your '.$result.'.';
            // Echos "You need to provide your name, zipcode, and phone."
        }

Preferment

Answer 5

$fruit = array('apple', 'banana', 'pear', 'grape');    
$commasaprated = implode(',' , $fruit);

Redblooded

The most simple answer. Why write tens of lines when you can do it in 1 line of code. – Centistere

Answer 6

I prefer to use an IF statement in the FOR loop that checks to make sure the current iteration isn't the last value in the array. If not, add a comma

$fruit = array("apple", "banana", "pear", "grape");

for($i = 0; $i < count($fruit); $i++){
    echo "$fruit[$i]";
    if($i < (count($fruit) -1)){
      echo ", ";
    }
}

Nigelniger

if the total count is just different than 4 ? – Figurehead

Answer 7

Sometimes you don't even need php for this in certain instances (List items each are in their own generic tag on render for example) You can always add commas to all elements but last-child via css if they are separate elements after being rendered from the script.

I use this a lot in backbone apps actually to trim some arbitrary code fat:

.likers a:not(:last-child):after { content: ","; }

Basically looks at the element, targets all except it's last element, and after each item it adds a comma. Just an alternative way to not have to use script at all if the case applies.

Palanquin

Answer 8

A functional solution would go like this:

$fruit = array('apple', 'banana', 'pear', 'grape');
$sep = ','; 

array_reduce(
    $fruits,
    function($fruitsStr, $fruit) use ($sep) {
        return (('' == $fruitsStr) ? $fruit : $fruitsStr . $sep . $fruit);
    },
    ''
);

Metempirics

Answer 9

Follow this one

$teacher_id = '';

        for ($i = 0; $i < count($data['teacher_id']); $i++) {

            $teacher_id .= $data['teacher_id'][$i].',';

        }
        $teacher_id = rtrim($teacher_id, ',');
        echo $teacher_id; exit;

Patrizius

Answer 10

If doing quoted answers, you can do

$commaList = '"'.implode( '" , " ', $fruit). '"';

the above assumes that fruit is non-null. If you don't want to make that assumption you can use an if-then-else statement or ternary (?:) operator.

Holcman

Answer 11

$letters = array("a", "b", "c", "d", "e", "f", "g"); // this array can n no. of values
$result = substr(implode(", ", $letters), 0);
echo $result

output-> a,b,c,d,e,f,g

Allegro