public function toJSON()
  {
    $json = json_encode( $this->toArray() );

    return str_replace(
      [
          '"%hoverCallback%"',
          '"%formatter%"',
          '"%dateFormat%"',
      ],
      [
          $this->hoverCallback,
          $this->formatter,
          $this->dateFormat,
      ],
      $json
    );
  }
public function toJSON()
  {
    $json = json_encode( $this->toArray() );

    return str_replace(
      [
          '"%hoverCallback%"',
          '"%formatter%"',
          '"%dateFormat%"',
      ],
      [
          $this->hoverCallback,
          $this->formatter,
          $this->dateFormat,
      ],
      $json
    );
  }
public function toJSON ( ) { $ json = json_encode ( $ this -> toArray ( ) ) ; return str_replace ( [ '"%hoverCallback%"' , '"%formatter%"' , '"%dateFormat%"' , ] , [ $ this -> hoverCallback , $ this -> formatter , $ this -> dateFormat , ] , $ json ) ; }
Return the jSON encode of this chart

@brief JSON

@return string
Return the jSON encode of this chart