function Html()
    {
        $text = $this->html;
        
        $pos = strpos($text, self::$placeholder);
        $phLength = strlen(self::$placeholder);
        while ($pos !== false && $this->currentChild)
        {
            $replacement = $this->RenderCurrentChild();
            $text = substr($text, 0, $pos) . $replacement . substr($text, $pos + $phLength);
            
            $this->currentChild = $this->tree->NextOf($this->currentChild);
            $pos = strpos($text, self::$placeholder, $pos  + strlen($replacement));
        }
        return $text;
    }