This function will convert the well-formed XML document in the file specified by filename to an object of class SimpleXMLElement. If any errors occur during file access or interpretation, the function returns FALSE.
You may use the optional class_name parameter so that simplexml_load_file() will return an object of the specified class. That class should extend the SimpleXMLElement class.
Since PHP 5.1.0 and Libxml 2.6.0, you may also use the options parameter to specify additional Libxml parameters.
Note: Libxml 2 unescapes the URI, so if you want to pass e.g. b&c as the URI parameter a, you have to call simplexml_load_file(rawurlencode('http://example.com/?a=' . urlencode('b&c'))). Since PHP 5.1.0 you don't need to do this because PHP will do it for you.
See also: simplexml_load_string()