如何从任意对象的无序数组中获取随机的任意对象？

Question

Here's the code I have:

if let photosData = parsedResult as? NSDictionary {
    var arrayOfPhotos = photosData.valueForKey("data")!
    // i want to do something like let photo = arrayOfPhotos.random
}

where photosData is

"data" =    
    (
        { 
            "id"= 1234;
            "name" = "Sam";
        },
        { 
            "id"= 4567;
            "name" = "John";
        },
        { 
            "id"= 1234;
            "name" = "Tony";
        }
    )

Now I am left with arrayOfPhotos which took the value of "data"

Questions:

How do I access a random object in arrayOfPhotos?

When I have a variable that xcode doesn't immediately tell me the type of, how do I get the type?

How do I log variables, objects while debugging? Do I just use print?

EDIT2: Heavily edited because the question was poorly written.

SOLVED:

I added "as? [AnyObject]" to arrayOfPhotos Declaration

if let photosData = parsedResult as? NSDictionary {
    var arrayOfPhotos = photosData.valueForKey("data")! as? [AnyObject]
    // i want to do something like let photo = arrayOfPhotos.random
}

now i can grab an object through arrayOfPhotos.first or grab at an index

Answer 1

arrayOfPhotos in this case is going to be an NSArray containing an ordered collection of NSDictionary . An NSArray is inherently ordered collection indexed by an integer as you get things out of them in the same order you put them into it. As opposed to an NSDictionary which is an unordered collection indexed by (in this case) an NSString. The dictionary is unordered because things don't necessarily come out in the same order you put them in, and in fact, come out in an unpredictable order if you were to iterate over all of the items in the dictionary.

To answer the exact question you asked, you would be better put to use:

if let photosData = parsedResult as? NSDictionary {
    if let arrayOfPhotos = photosData.valueForKey as? [[String:AnyObject]] {
        // At this point, arrayOfPhotos is an array of dictionaries, so we use direct int indexing:
        let firstPhoto = arrayOfPhotos[0]
        let nthPhoto = arrayOfPhotos[n]

        // Both firstPhoto and nthPhoto now have the type [String:AnyObject], or in otherwords
        //  they map a String to anything, anything because "id" is an int, and "name" is a String
        let firstId = firstPhoto["id"] as! Int
        let firstName = firstPhoto["name"] as! String
    }
}