Remove last comma from an array

Question

In this Code below I have a array that returns a comma to me at the end exe: '98602','98603','98604',

How can I remove this comma?

 if (isset($_POST['checkbox'])) {
 foreach ($_POST['checkbox'] as $key => $value) {
    $id = mysql_real_escape_string($value);

    $regra = "'{$id}',";
    echo $regra;       
 }}

Answer 1

After the foreach use replace to remove the last character:

If last parameter(lenght) is negative it will remove the characters at the end of the string. Don’t forget to start $regra otherwise its value will always be 'reset' with each round of the.

 if (isset($_POST['checkbox'])) {
    $regra = '';
    foreach ($_POST['checkbox'] as $key => $value) {
      $id = mysql_real_escape_string($value);

      $regra .= "'{$id}',";

    }
    $regra = substr($regra, 0, -1);
    echo $regra;
 }

Another way to format this string at once is to combine the first and last simple quote between implode call:

$arr = array('98602','98603','98604'); // equivalente o $_POST
$novo = "'". implode("','", $arr) ."'";
echo 'implode '. $novo;

Exit:

'98602','98603','98604'

Answer 2

There are several ways, even you can make an algorithm that is not inserted. I think the easiest would be the rtrim():

if (isset($_POST['checkbox'])) {
    foreach ($_POST['checkbox'] as $key => $value) {
        $id = mysql_real_escape_string($value);
        $regra = "'{$id}',";
        echo $regra;       
    }
    rtrim($regra, ',');
}

I put in the Github for future reference.

Answer 3

Based on what @Maniero mentioned, one way is not to insert the comma, instead of removing it. Note that the code gets longer than with rtrim:

$regra = '';
$separador = '';
if ( isset( $_POST['checkbox'] ) ) {
   foreach ( $_POST['checkbox'] as $value ) {
      $regra .= $separador."'".mysql_real_escape_string( $value )."'";
      $separador = ',';
   }
}
echo $regra;       

I took the opportunity to give a little optimized taking the echo of the main logic and removing the $key => and the $id which are not necessary in this case.

Answer 4

You can map this array and then merge the array elements with commas in the middle:

$func = function($value) {
     $id = mysql_real_escape_string($value);
     return "'{$id}'";
};

$ids = array_map($func, $_POST['checkbox']);
echo implode(",", $ids);

You have other correct answers, this is another approach I prefer.
The if (isset($_POST['checkbox'])) it’s still necessary, that part you can keep.

Answer 5

Another way to solve it would also be

if (isset($_POST['checkbox'])) {
  $regra = "";
  foreach ($_POST['checkbox'] as $key => $value) {
    $id = mysql_real_escape_string($value);

    $regra .= ($regra != "" ? "," : "") . "'{$id}'";
  }
 }