Swift5結構陣列中的嵌套排序

這是我的模型看起來像

struct ContactModel{
    var alphabet: String
    var users: [UserModel]
}

struct UserModel{
    var firstname: String
    var lastname: String
}

sort在這里使用按字母順序排序作業正常是代碼：

contactArray.sort{ $0.alphabet < $1.alphabet }

現在，我想在UserModel firstname 嘗試嵌套排序的基礎上對升序或降序進行排序，但給了我不同的錯誤，例如

Comparable and Binary operator '<' cannot be applied to two '[UserModel]' operands

我在 StackOverflow 上搜索了這個，但沒有找到嵌套排序和運算元錯誤解決方案。

我試過這種方式

let sortedStudents = contactArray.sorted { (lhs: ContactModel, rhs: ContactModel) -> Bool in
                let users1 = lhs.users.sorted(by: {
                    $0.firstname.lowercased() < $1.firstname.lowercased()
                })
                let users2 = rhs.users.sorted(by: {
                    $0.firstname.lowercased() < $1.firstname.lowercased()
                })
                
                return users1 < users2
            }

但它不作業。這里唯一的問題是我無法在這里進行嵌套排序，我想對 UserModel 的名字和 We have ContactModelArray進行排序

var contactArray = [ContactModel](){
        didSet{
            
            contactArray.sort{ $0.alphabet < $1.alphabet } //Simple Sort working fine.
            
            let sortedStudents = contactArray.sorted { (lhs: ContactModel, rhs: ContactModel) -> Bool in
                let users1 = lhs.users.sorted(by: {
                    $0.firstname.lowercased() < $1.firstname.lowercased()
                })
                let users2 = rhs.users.sorted(by: {
                    $0.firstname.lowercased() < $1.firstname.lowercased()
                })
                
                return users1 < users2
            }
            
            self.tableView.reloadData()
        }
    }

陣列包含這個

 func getAllContacts() -> [ContactModel]{
        return [
            ContactModel(alphabet: "B", users: [
                UserModel(firstname: "Bhaswar", lastname: "Patel"),
                UserModel(firstname: "Bunty", lastname: "Patel")
            ]),
            ContactModel(alphabet: "N", users: [
                UserModel(firstname: "Nilesh", lastname: "Darji")
            ]),
            ContactModel(alphabet: "Y", users: [
                UserModel(firstname: "Yogesh", lastname: "Patel"),
                UserModel(firstname: "Yash", lastname: "Patel")
            ])
        ]
    }

結果：

字母部分排序作業正常，現在需要使用名字對用戶進行排序，Yash然后是第一個Yogesh

任何建議表示贊賞。謝謝！

uj5u.com熱心網友回復：

下面的代碼ContactModel首先根據字母表對陣列進行排序。然后，它將這個排序的陣列映射到一個新陣列，該UserModel陣列也被排序。

contactArray.sort { $0.alphabet < $1.alphabet }
let fullySorted = contactArray.map( { ContactModel(alphabet: $0.alphabet, users: $0.users.sorted { $0.firstname < $1.firstname }) } )

的map和sort功能也可以交換，即，第一映射到一個新的陣列，然后分選基于字母表。原始陣列：

var contactArray = [
    ContactModel(alphabet: "B", users: [
        UserModel(firstname: "Bhaswar", lastname: "Patel"),
        UserModel(firstname: "Bunty", lastname: "Patel")
    ]),
    ContactModel(alphabet: "N", users: [
        UserModel(firstname: "Nilesh", lastname: "Darji")
    ]),
    ContactModel(alphabet: "Y", users: [
        UserModel(firstname: "Yogesh", lastname: "Patel"),
        UserModel(firstname: "Yash", lastname: "Patel")
    ])
]

將變成（Yash 和 Yogesh 現在按字母順序排列）：

var contactArray = [
    ContactModel(alphabet: "B", users: [
        UserModel(firstname: "Bhaswar", lastname: "Patel"),
        UserModel(firstname: "Bunty", lastname: "Patel")
    ]),
    ContactModel(alphabet: "N", users: [
        UserModel(firstname: "Nilesh", lastname: "Darji")
    ]),
    ContactModel(alphabet: "Y", users: [
        UserModel(firstname: "Yash", lastname: "Patel"),
        UserModel(firstname: "Yogesh", lastname: "Patel")
    ])
]

如果還有另一個ContactModelwith alphabet = "A"，那么這將是contactArray.

如果您真的需要，您甚至可以將其縮減為一行代碼。但是，我不會推薦它，因為排序和映射對于不熟悉它的人來說很難閱讀。

// Single line of code solution (I wouldn't recommend this because of readability)
let fullySorted = contactArray.sorted { $0.alphabet < $1.alphabet }.map( { ContactModel(alphabet: $0.alphabet, users: $0.users.sorted { $0.firstname < $1.firstname }) } )

標籤：数组 迅速 排序 多维数组

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