Insertion of a dot every 5 characters

Question

I have the following string: "AAAAABBBBBCCCCC"

There is a script that puts a dot "." every 5 characters?
In case this script would return: "AAAAA.BBBBB.CCCCC."

Answer 1

A solution is the function chunk_split() which serves precisely to divide the string in smaller pieces:

$str = chunk_split("AAAAABBBBBCCCCCDDDDD", 5, '.');

Example in Ideone:

var_dump($str); // AAAAA.BBBBB.CCCCC.DDDDD.

^{Note: I’m suggesting this function because in your question you asked not only to add the . each X positions, but for the result end with .. With this function, you meet both requirements.}

Answer 2

You can do it this way:

<?php 
    $string = "AAAAABBBBBCCCCC";
    $array = str_split($string, 5); 
    $novaString = implode(".", $array);
    echo $novaString;
?> 

Explaining what happens: You have separated the string into several Strings, and stored it within an array called $array. The result is:

$array[0] has AAAAAAA values

$array[1] has BBBBB values

$array[2] has CCCCC values

And after the separation in the arrays, the implode is used to concatenate the strings stored in the array with the dot (.). I hope it helped..

Answer 3

Another way to add a string based on an interval(5 characters) is to use the function wordwrap. The third parameter is the character to be inserted and the fourth forces php to add the character in the exact range, because the purpose of the function is to make the addition between words and how your string is one thing only the fourth parameter is mandatory.

$str = "AAAAABBBBBCCCCCDDDDD";
$intervalo = 5;
$str_formatada = wordwrap($str, $intervalo, '.', true);

echo $str_formatada;

Exit:

AAAAA.BBBBB.CCCCC.DDDDD

phpfiddle - example

---

Example of the fourth parameter:

1 - Omitted

$str = 'A very long woooooooooooord';
$str_formatada = wordwrap($str, 3, "<br>");

echo $str_formatada;

Exit:

A
very
long
woooooooooooord

As the words were smaller or larger than the specified range(3) the function ended up adding <br> among them. See how it works when the fourth parameter is marked as true, now the string is broken to exactly 3 characters even if it cuts or ruins the word.

2- With the fourth parameter

Exit:

A
ver
y
lon
g
woo
ooo
ooo
ooo
ord

Answer 4

Since they raised the hare on multibyte, I’ll leave an alternative with such support:

$string = 'aaaaabbbbbcccccdddddeeeee1111122222maçãsefeijões';

$new = implode(

    '.',

    preg_split(

        '/(.{5})/us',

       $string, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE
    )
);

This produces:

string 'aaaaa.bbbbb.ccccc.ddddd.eeeee.11111.22222.maçãs.efeij.ões' (length=60)