<?php
 
    function removeSpecialChars($string){
      //List (Array) of special chars
	  $pattern = array("/([áàãâä])/","/([ÁÀÃÂÄ])/","/([éèêë])/","/([ÉÈÊË])/","/([íìîï])/","/([ÍÌÎÏ])/","/([óòõôö])/","/([ÓÒÕÔÖ])/","/([úùûü])/","/([ÚÙÛÜ])/","/(ñ)/","/(Ñ)/","/(ç)/","/(Ç)/","/([\\'\\\"\\^\\~\\;\\:\\°\\?\\&\\*\\+\\@\\#\\$\\%\\!\\\\\\/\\(\\)\\|\\=\\.\\,])/");
 
      //List (Array) of letters
      $replacement = array('a', 'A', 'e', 'E', 'i', 'I', 'o', 'O', 'u', 'U', 'n', 'N', 'c', 'C', '');
 
      return preg_replace($pattern , $replacement, $string);
    }
 
echo removeSpecialChars("áçõ/\\?&"); 

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