PHP実装explort()機能の詳細

 
  
/** 
  
 * PHP   explort()       
  
 */ 
  
$str = ',1,2,3,4,321321,aaa,bbb'; 
  
function myExplode($seg,$str,$limit=0){ 
  
   $_ret = array(0=>''); 
  
   $len = strlen($str); 
  
   $slen = strlen($seg); 
  
   $_limit = 0; 
  
   for($i=0; $i      if(substr($str,$i,$slen) == $seg ){ 
  
          $_limit++; 
  
          $i += $slen-1; 
  
          continue; 
  
      }else{ 
  
          $_ret[$_limit] .= $str[$i]; 
  
      } 
  
   } 
  
   if($limit < 0 ) 
  
      $_ret = array_slice($_ret, 0 , $limit ); 
  
   else{ 
  
      $_ret = $limit >= count($_ret) ? $_ret :  array_merge(array_slice($_ret, 0 , $limit-1 ), array(implode( $seg , array_slice($_ret,$limit-1)))); 
  
   } 
  
   return $_ret; 
  
} 
  
var_dump(myExplode("4",$str)); 
  
echo "
"; 
  
var_dump(explode("4",$str)); 
  
echo "
"; 
  
?>