Returns the content of the receiver as a string value.
- macOS 10.4+
If the receiver is a node object of element kind, the content is that of any text-node children. This method recursively visits elements nodes and concatenates their text nodes in document order with no intervening spaces. If the receiver’s content is set as an object value, this method returns the string value representing the object. If the object value is one of the standard, built-in ones (
NSCalendar, and so on), the string value is in canonical format as defined by the W3C XML Schema Data Types specification. If the object value is not represented by one of these classes (or if the default value transformer for a class has been overridden), the string value is generated by the
NSValue registered for that object type.