2. Traversable (traversal) interface

: This article mainly introduces the 2 Traversable (traversal) interface. if you are interested in the PHP Tutorial, refer to it.

  Prop = 'hello'; var_dump ($ objinstanceof Traversable); // false

Purpose: check whether a class can be traversed using foreach. Php code is unavailable. Only the internal PHP class (Class written in C) can directly implement the traversal using Iterator or IteratorAggregate interface in the Traversable interface php code. This interface does not have any method. it serves only as the basic interface for all traversal classes.

'). AddClass ('pre-numbering '). hide (); $ (this ). addClass ('Has-numbering '). parent (). append ($ numbering); for (I = 1; I <= lines; I ++) {$ numbering. append ($ ('

'). Text (I) ;}; $ numbering. fadeIn (1700) ;}) ;}; script

The above introduces the 2 Traversable (traversal) interface, including the content, hope to be helpful to friends who are interested in PHP tutorials.