How to compare variable value with increment operator?

Question

Follows the function:

$conteudo = $textodobanco;
function addBanner($i) {
    static $conta1 = 0;
    $retorno = $i[0];
    if (++$conta1 == 5) {
        $retorno .= '<b>BANNER 1</b>';
    }
    return $retorno;
}

$txt = preg_replace_callback('#(<br />)#', 'addBanner', $conteudo);

The above function works perfectly, however, I need that instead of using the number 5 expressed in the comparison, that it be replaced by a variable, so as to dynamize the system I am developing.

However, all attempts like below on replacing the number 5 by a variable did not work, ie the function does not return any result.

Substitution by variable, however, without success

function addBanner($i) {
    static $conta1 = 0;
    $retorno = $i[0];
    if (++$conta1 == $numerovar) {
        $retorno .= '<b>BANNER 1</b>';
    }
    return $retorno;
}

Answer 1

To make the comparison with a variable first you need either create it or pass it as Parameter...

Follow an example passing it as Parameter:

function addBanner($i, $numerovar)
{
   static $conta1 = 0;
   $retorno = $i[0];
   if(++$conta1 == $numerovar)
   {
      $retorno .= '<b>BANNER 1</b>';
   }
   return $retorno;
}

Follow an example Creating she:

function addBanner($i)
{
   static $conta1 = 0;
   $retorno = $i[0];
   $numerovar = 10;
   if(++$conta1 == $numerovar)
   {
      $retorno .= '<b>BANNER 1</b>';
   }
   return $retorno;
}