Does Apple provides any library or API to manipulate the CalDAV?

I want to ask a question about the iPhone applicati开发者_运维问答on. I am going to write a program which is related to a calendar function. I want to use the CalDAV to do this. However, I am not familiar with the iOS environment. Does the apple provides any library or API for the developers to write the program by manipulating the CalDAV? Thank you very much.

With iOS 4 you can access the users calendar with Event Kit. But you can't directly work with CalDAV. You have to use a third party library for that.