为什么`$ session-> set（）`有两个参数？

Question

I'm new to Symfony2. I was going through the documentation, reading about sessions. Strange thing I've noticed that a session in Symfony2 can hold two seperate strings like this:

$session->set('foo', 'bar');

I was hoping the documentation would explain this but all it says is:

// store an attribute for reuse during a later user request

Could someone explain this to me, please?

Answer 1

$session->set('foo', 'bar'); will set the attribute named foo to value bar.

You can read more about session management in the documentation.