我如何“使用” IteratorAggregate接口，PHP找不到它？

Question

I have a class that I want to implement IteratorAggregate. I declare:

class Email implements IteratorAggregate {

but when I rung the code I get:

Attempted to load interface "IteratorAggregate" from namespace "Companyname\\ConsoleBundle\\Entity". Did you forget a "use" statement for another namespace?

So what name space should I adding to implelement the 'IteratorAggregate' interface. None of the examples I've seen include any use or require statements for it and it should be included as standard in PHP5 so it's not an installation issue.

Any ideas what I'm doing wrong?

Answer 1

当您使用自己的名称空间并且要使用标准类时，必须像这样拼写

class Email implements \IteratorAggregate {

Answer 2

To "use" classes from the global namespace, prefix them with a backslash:

use \IteratorAggregate;

class Email implements IteratorAggregate { ... }