how can i join in array same id in swift? - arrays

Question

i want to make like a group array
struct songST {
var singerid:[Int]
var songname:[String]
var songembeded:[String]
}
**fist item;**
songST(singerid: "1", songname: ["Its my life"], songembeded: ["url1"])
**seconditem=**
songST(singerid: "1", songname: ["Always"], songembeded: ["url2"])
**i want to make join like this**
songST(singerid: "1", songname: ["Its my life","Always"], songembeded: ["url1","url2"])
if there was same singerid than will join
how can i do that? Please Help me.

Answer 1

I think you can improve how data is modeled.
A song consists of the following fields:
singer id
song name
song url
So it would make sense to create a model with exactly those fields, as opposed to creating an array for each of them:
struct Song {
let singerId: Int
let songName: String
let songEmbedded: String
}
Next, you need a data container for all your songs, which must be grouped by singer. The easiest way is to use a dictionary, whose key is the singer id and the value is an array of Song.
Rather than manually creating and handling the dictionary, it's better if a proper data container is created:
struct Singers {
var singers: [Int : [Song]] = [:]
mutating func addSong(song: Song) {
if self.singers[song.singerId] == nil {
self.singers[song.singerId] = []
}
self.singers[song.singerId]?.append(song)
}
func getSongs(singerId: Int) -> [Song] {
if self.singers[singerId] == nil {
return []
}
return self.singers[singerId]!
}
}
The Singers struct contains a dictionary property, and two method:
addSong adds a song, assigning it to the proper array identified by the key (singer id)
getSongs returns an array of songs for a singer id
Some sample code taken from a storyboard:
let s1 = Song(singerId: 1, songName: "Its my life", songEmbedded: "url1")
let s2 = Song(singerId: 1, songName: "Always", songEmbedded: "url2")
let s3 = Song(singerId: 2, songName: "Another", songEmbedded: "url3")
var singers = Singers()
singers.addSong(s1)
singers.addSong(s2)
singers.addSong(s3)
singers.getSongs(1) // Returns an array of 2 items
singers.getSongs(2) // Returns an array of 1 item
singers.getSongs(3) // Returns an empty array (no song for singer 3)

Answer 2

Easy.
You asked - "if there was same singerid than will join".
Make a function that uses that if statement:
func combineFirstSongST(firstSongST: songST, withSecondSongST secondSongST: songST) -> songST?
{
if firstSongST.singerid != secondSongST.singerid
{
return nil
}
else
{
return songST(singerid: firstSongST.singerid, songname: firstSongST.songName + secondSongST.songName, songembeded: firstSongST.songembeded + secondSongST.songembeded) //single statement
}
}
You should use camel case.