A question in the php Manual

A question in the php Manual is used:
Is this a static method?
Or does it only indicate that this method exists in this class?

Reply to discussion (solution)

Indicates that this method is available.
Most of them cannot be used without instantiation.

Indicates that this method exists in the class. whether it is a static method depends on the document. most of them are not.

$ Memcache_obj = memcache_connect ("localhost", 11211);/* process-oriented programming API */memcache_add ($ memcache_obj, 'Var _ key', 'Test variable', false, 30);/* object-oriented programming API */$ memcache_obj-> add ('Var _ key', 'Test variable', false, 30 );

Thank you. Another question is: is self and _ CLASS _ in the CLASS different?

_ CLASS _ only the CLASS name is a string
Self is a class reference.

@ AO xuexingfeng: Is $ a used here? If yes, the variable is not assigned a value. why not report an error?

A variable is defined, but no value is assigned. Not an error.