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iOS

Simen Anthonsen
Simen Anthonsen
1,097 Points
Posted by Simen Anthonsen
Simen Anthonsen
1,097 Points

Check if CKRecord array contains a certain record

I´ve got an CKRecord array consisting of movie objects. How can I, for example, check if the array contains a movie with the title "Jaws" ?

2 Answers

jcorum
jcorum
71,828 Points
jcorum
jcorum
71,828 Points

There are a number of different ways to do this. Here's one that uses a loop inside a function:

//create struct, could also be a class
struct Movie {
    var title: String  //limited to one stored property, but could easily have many more
}

//create movies
var m1 = Movie(title: "Star Wars")
var m2 = Movie(title: "Pride and Prejudice")
var m3 = Movie(title: "Casablanca")

//create array of movies
let CKRecords = [m1, m2, m3]

//create function to check if array contains a movie
func checkMovie(title: String) -> Bool {
    var contains = false
    for movie in CKRecords {
        if title == movie.title {
            contains = true
        }
    }
    return contains
}

//test
checkMovie("Star Wars")
checkMovie("Harry Potter")
Simen Anthonsen
Simen Anthonsen
1,097 Points
Simen Anthonsen
Simen Anthonsen
1,097 Points

CKRecords is of type CKRecord as in CloudKitRecord. What I am doing right now, is what you suggest and loop through the array. But Im wondering if there is a way, that is like this:

    var movies = [CKRecord]()
    //movies is the CKRecord Array

    if movies.contains(CKRecord.whereKey"Title" == "Jaws") {
   ///Do stuff
    }
jcorum
jcorum
71,828 Points
jcorum
jcorum
71,828 Points

The contains() method works with Ints, Strings, etc., as expected:

var names = ["B","C"]
names.contains("G")  //false
names.contains("B")  //true

For arrays of structs, classes (and I don't know what else) contains() requires a different kind of parameter: predicate: (protocol<>) throws -> Bool (i.e., a closure). You can also use the filter() method.

CKRecords.contains({ $0.title == "Casablanca" })  //true
CKRecords.filter( { $0.title == "Casablanca" } )  //true