PHP中的聚合和委派是什么？

I was wondering what these terms are in php...I looked up google but couldn't find any good answers. I would appreciate if someone here can help me about it. Thanks a lot.!!!

Aggregation and delegation are general object-oriented programming concepts.

Here are a few links you might consider perusing:

• http://en.wikipedia.org/wiki/Aggregation_(object-oriented_programming)#Aggregation
• http://en.wikipedia.org/wiki/Delegation_(programming)
• http://php.net/manual/en/language.oop5.php (This is just the OOP portion of the PHP manual, where aggregation and delegation would be relevant)

There is no significant difference in programming language for this terms:

http://en.wikipedia.org/wiki/Delegation_%28programming%29

http://en.wikipedia.org/wiki/Aggregation_%28object-oriented_programming%29#Aggregation

Not to totally necro-post (can't comment on the answer I wanted to add to), but while looking through @froggythefrog's answer I came across another Wikipedia article that's a little more pointed and features a php-specific example.

http://en.wikipedia.org/wiki/Delegation_pattern

In short Aggregation and Delegation are design patterns where other objects are members of, or linked to, a class so that their functionality can easily be accessed in the overarching class.