Question

我正在尝试按字母顺序和组名的顺序对数组进行排序

我的名单是：

Name: A
Group: cats

Name: B
Group: dogs

Name: C
Group: cats

我已经按照姓名的字母顺序进行了操作，并向我显示了以下顺序：

A
cats

B
dogs

C
cats

但是我偏头痛试图按组对它们进行排序，例如：

A
cats

C
cats

B
dogs

到目前为止，我尝试按字母顺序和组顺序进行操作：

case alpha:
    results.sorted { $0.first_name < $1.first_name }
case grouped:
    results.sorted { $0.group_name == $1.group_name }

Answer 1

尝试一下：

results.sorted {($0.group_name, $0.first_name) < ($1.group_name, $1.first_name)}

示例：

struct Item {
    var first_name: String
    var group_name: String
}

let results = [
    Item(first_name: "A", group_name: "cats"),
    Item(first_name: "B", group_name: "dogs"),
    Item(first_name: "C", group_name: "cats")
]
let sortedResult = results.sorted {($0.group_name, $0.first_name) < ($1.group_name, $1.first_name)}
print(sortedResult)
//->[SortGroups.Item(first_name: "A", group_name: "cats"), SortGroups.Item(first_name: "C", group_name: "cats"), SortGroups.Item(first_name: "B", group_name: "dogs")]

Carpsen90当前代码失败的示例。

struct Animal {
    let Name: String
    let Group: String
}

let animals = [
    Animal(Name: "B", Group: "rats"),
    Animal(Name: "C", Group: "dogs"),
    Animal(Name: "E", Group: "cats"),
    Animal(Name: "B", Group: "dogs"),
    Animal(Name: "A", Group: "cats"),
    Animal(Name: "C", Group: "dogs"),
    Animal(Name: "E", Group: "cats"),
    Animal(Name: "A", Group: "dogs"),
    Animal(Name: "B", Group: "dogs"),
    Animal(Name: "B", Group: "dogs"),
    Animal(Name: "D", Group: "cats"),
    Animal(Name: "A", Group: "cats"),
    Animal(Name: "B", Group: "cats"),
    Animal(Name: "B", Group: "dogs"),
    Animal(Name: "D", Group: "rats"),
    Animal(Name: "A", Group: "rats"),
    Animal(Name: "B", Group: "dogs"),
    Animal(Name: "D", Group: "dogs"),
    Animal(Name: "A", Group: "dogs"),
    Animal(Name: "A", Group: "rats")
]

let result = animals.sorted(by: {$0.Group < $1.Group}).sorted(by: {$0.Group == $1.Group && $0.Name < $1.Name })
print("[\n  "+result.map {String(describing: $0)}.joined(separator: ",\n  ")+"\n]")

输出：

[
  Animal(Name: "E", Group: "cats"),
  Animal(Name: "A", Group: "dogs"),
  Animal(Name: "A", Group: "dogs"),
  Animal(Name: "B", Group: "dogs"),
  Animal(Name: "B", Group: "dogs"),
  Animal(Name: "B", Group: "dogs"),
  Animal(Name: "B", Group: "dogs"),
  Animal(Name: "B", Group: "dogs"),
  Animal(Name: "C", Group: "dogs"),
  Animal(Name: "C", Group: "dogs"),
  Animal(Name: "A", Group: "cats"),
  Animal(Name: "B", Group: "cats"),
  Animal(Name: "D", Group: "cats"),
  Animal(Name: "E", Group: "cats"),
  Animal(Name: "D", Group: "dogs"),
  Animal(Name: "A", Group: "cats"),
  Animal(Name: "A", Group: "rats"),
  Animal(Name: "A", Group: "rats"),
  Animal(Name: "B", Group: "rats"),
  Animal(Name: "D", Group: "rats")
]

对相同的输入使用元组比较：

let result2 = animals.sorted {($0.Group, $0.Name) < ($1.Group, $1.Name)}
print("[\n  "+result2.map {String(describing: $0)}.joined(separator: ",\n  ")+"\n]")

输出：

[
  Animal(Name: "A", Group: "cats"),
  Animal(Name: "A", Group: "cats"),
  Animal(Name: "B", Group: "cats"),
  Animal(Name: "D", Group: "cats"),
  Animal(Name: "E", Group: "cats"),
  Animal(Name: "E", Group: "cats"),
  Animal(Name: "A", Group: "dogs"),
  Animal(Name: "A", Group: "dogs"),
  Animal(Name: "B", Group: "dogs"),
  Animal(Name: "B", Group: "dogs"),
  Animal(Name: "B", Group: "dogs"),
  Animal(Name: "B", Group: "dogs"),
  Animal(Name: "B", Group: "dogs"),
  Animal(Name: "C", Group: "dogs"),
  Animal(Name: "C", Group: "dogs"),
  Animal(Name: "D", Group: "dogs"),
  Animal(Name: "A", Group: "rats"),
  Animal(Name: "A", Group: "rats"),
  Animal(Name: "B", Group: "rats"),
  Animal(Name: "D", Group: "rats")
]

Swift数组按字母顺序和组顺序排序

1 个答案: