How to combine arrays depending on user selection? - ios

Question

I want to see what user selected like the name of book and its assocaited chapters
I did this
struct bookChpt {
var book:[String] = []
var chapter:[[Int]] = []
}
let chptSelected = [bookChpt(book:bookArr,chapter:chptArr)]
var bookArr:[String] = []
var chptArr:[[Int]] = []
I have this in viewDidLoad()
if let bTitle = result.value(forKey: "bookTitle") as? String
{
bookArr.append(bTitle)
}
if let cNo = result.value(forKey: "chpNo") as? [Int]
{
chptArr.append(cNO)
}
print(chptSelected)
I am getting this
bookChpt( book: ["Hobbit", "LOTR"], chapter: [[3,5],4])
but I like to see this
["Hobbit", 3, 5], ["LOTR", 4]

Answer 1

There are a couple of possibilities. You could add a function to the struct to display its contents in the way you want:
struct BookChapter {
var book:[String] = []
var chapter:[[Int]] = []
func display() -> [[Any]] {
var output = [[Any]]()
for i in 0..<book.count {
output.append([book[i], chapter[i]])
}
return output
}
}
Or you could modify the structure of the struct to contain the book and chapters as tuples:
struct BookChapter {
var book:[(String, [Int])]
}
Going a bit further, anywhere you see a loop - such as in the display function above - you might also consider using map to achieve the same thing:
func display() -> Any {
return book.enumerated().map { $0.element + " " + chapter[$0.offset].description }
}

Answer 2

If you use an Dictionary like this, you can print the key and value whatever way you wanted.
var bookChapters = [String: [Int]]()
bookChapters["Hobbit"] = [1,2,3]
bookChapters["Hobbit"]?.append(contentsOf: [4])
for (book, chapter) in bookChapters {
print("\(book): \(chapter)")
}

Answer 3

Change your struct to
struct BookChapt {
var book: String = ""
var chapter: [Int] = []
}
and in viewDidLoad()
var bookName = ""
var chapters:[Int] = []
if let bTitle = result.value(forKey: "bookTitle") as? String
{
bookName = bTitle
}
if let cNo = result.value(forKey: "chpNo") as? [Int]
{
chapters = cNo
}
let chptSelected = BookChapt(book: bookName, chapter: chapters)
print(chptSelected)