如何将字符串数组写入单个格式化的字符串中

Question

I have an array of items:

array(
    'apples',
    'oranges',
    'pineapples'
)

that I would like to format like so: "Some of my favorite fruits are apples, oranges and pineapples"

So, using PHP I would like to be able to transform that array into a reader friendly apples, oranges and pineapples.

At first I thought I might be able to use array_map but i'm not sure how I would go about telling what the last and 2nd to last items are (it's easy to add a , after each item with array_map, however you wouldn't want a comma before the last item)

Thoughts?

Answer 1

Divide the problem to conquer it: Take out the last element, create the comma separated list and then add the last element.

$array = array(
    'apples',
    'oranges',
    'pineapples'
);

$last = array_pop($array);
echo implode(', ', $array), ' and ', $last; # apples, oranges and pineapples

Naturally this only makes sense when there are at least two values in the array. Functions used: implode^Docs (probably more suitable than array_map in this case) and array_pop^Docs.

---

On the other hand, if the values do not contain any , you can first create a comma separated string with the implode function and then use a regular expression to replace the last comma with and.

That done will also work on arrays that have less than 2 elements. I do this in a loop that removes one element from the array in each step so that it shows how it behaves:

$array = array(
    'apples',
    'oranges',
    'pineapples'
);

foreach($array as $v)
{
    echo preg_replace('(,([^,]*)$)', ' and$1', implode(', ', $array)), "
";
    array_pop($array);
}

Output:

apples, oranges and pineapples
apples and oranges
apples