在 iOS Swift 中对自定义对象进行排序

Question

我试图根据 studentId 按升序对对象进行排序，但它不是排序。 请检查我下面的代码。

class ViewController: UIViewController {
    var sortObjects = [Int]()

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
        getData()
    }

    func getData(){
        let url = URL(string: "https://next.json-generator.com/api/json/get/NJYwQJDU_")!
        var request = URLRequest(url: url, cachePolicy: .reloadIgnoringCacheData,timeoutInterval: 10000)

        URLSession.shared.dataTask(with: request) { (data, response, error) in
            if error != nil {
                print(error!)
                return
            }

            do {
                guard let data = data else{return}

                if let jsonData = try JSONSerialization.jsonObject(with:data, options: []) as? [[String:AnyObject]] {
                    for item in jsonData{
                        if let ids =  item["studId"] as? AnyObject{
                            self.sortObjects.append(ids as! Int)
                        }
                    }
                    print("before sort:\(self.sortObjects)")
                    print("sorted:\(self.sortObjects.sorted())")
                    for item in jsonData{
                        if(self.sortObjects.sorted().contains(item["studId"] as! Int))
                        {
                            print(item)
                        }
                    }
                }
            } catch let error as NSError {
                print(error)
            }
        }.resume()

    }

}

我尝试根据 studentId 按升序对对象进行排序。 我得到低于输出，但它正在对单个元素数组进行排序。 以上不适用于排序对象。 请检查一次。

Output:
before sort:[5, 3, 9, 1]

sorted:[1, 3, 5, 9]

["studId": 5, "seqNumber": 3071414307, "studName": Bob David]
["seqNumber": 3071414310, "studName": Ruther, "studId": 3]
["studId": 9, "seqNumber": 3071424307, "studName": Smith]
["seqNumber": 3076414307, "studName": Charles, "studId": 1]

Expected Output:

["seqNumber": 3076414307, "studName": Charles, "studId": 1]
["seqNumber": 3071414310, "studName": Ruther, "studId": 3]
["studId": 5, "seqNumber": 3071414307, "studName": Bob David]
["studId": 9, "seqNumber": 3071424307, "studName": Smith]

Answer 1

试试这个：

if let jsonData = try JSONSerialization.jsonObject(with: data, options: []) as? [[String : Any]] {
    let sortedObjects = jsonData.sorted(by: { ($0["studId"] as! Int) < ($1["studId"] as! Int) })
    for object in sortedObjects {
        print(object)
    }
}