【Xcode/Swift】音声ファイルの再生

import UIKit
import AVFoundation

class GitTestViewController: UIViewController {

    @IBOutlet var playSoundButton: [UIButton]!

    private var player: AVAudioPlayer?

    override func viewDidLoad() {
        super.viewDidLoad()
        //ボタンを角丸にする
        playSoundButton.forEach({ $0.layer.cornerRadius = 20.0 })
    }

    //押されたボタンのタグ番号で判断する
    @IBAction func playSoundAction(_ sender: UIButton) {
        switch sender.tag {
        case 1:
            playSoundFile(fileName: "warning")
            print("警告音")
        case 2:
            playSoundFile(fileName: "policecar")
            print("パトカー")
        case 3:
            playSoundFile(fileName: "cow")
            print("ウシ")
        case 4:
            playSoundFile(fileName: "station")
            print("改札")
        default:
            break
        }
    }

    //【fileName】が変わるだけなので関数で切り分ける
    private func playSoundFile(fileName: String) {
        if let soundData = NSDataAsset(name: fileName) {
            do {
                player = try AVAudioPlayer(data: soundData.data)
                player?.play()
            } catch {
                print("再生実行エラー")
            }
        }
    }

}