(PHP 5 >= 5.2.0)
XMLReader::setSchema — Validate document against XSD
Use W3C XSD schema to validate the document as it is processed. Activation is only possible before the first Read().
The filename of the XSD schema.
如果成功则返回 TRUE，失败则返回 FALSE。
Issues E_WARNING if libxml was built without schema support, the schema contains errors or if XMLReader::read() has already been called.
This function is only available when PHP is compiled against libxml 20620 or later.