Someone

			}else{
				if($this->min_length!="" && $this->max_length!=""){
					$regex="^[$regex]\{".$this->min_length.",".$this->max_length."}$";
				}else if($this->min_length!=""){
					$regex="^[$regex]\{".$this->min_length.",}$";
				}else if($this->max_length!=""){
					$regex="^[$regex]\{0,".$this->max_length."}$";
				}else{
					$regex="^[$regex]*$";
				}
			}
			return ereg($regex,$string);