Question

What is the best, most concise coding practice for eliminating the final comma when generating a comma-delimted list in a typical for loop? This comes up ALL THE TIME and I cannot stand writing so many extra lines of code for something so simple… there must be a better technique/pattern.

foreach ($list as $item)
{
    echo "'".$item . "',";
}

What is the best way (using PHP and/or JS) to make the above code produce a comma everywhere but the last iteration?

Right now I am doing something like this:

$total = count($images);
$i=0;
foreach ($list as $item)
{
    $i++;
    echo "'".$item."'";
    if ($i<$total) echo ',';
}

But this adds FOUR LINES OF CODE for something so simple…

Answer 1

User implode() function to achieve this. Sometimes it’s also necessary to put something around, for example, to quote SQL fields’ values:

$fields = '"' . join('", "', $values) . '"';

And for JavaScript use Array.join() method (W3C):

var implodedString = someArray.join(',')