Swift上的NSArray排序函數

Question

我有一個名爲People的數組。人物數組包含Person對象。我想基於firstName升序排列數組。

var people :[Person] = [] 

people.sort { $0.firstName > $1.firstName } 

我得到以下錯誤：

() is not convertible to [Person] 

Answer 1

我相信，你只需要初始化時，更明確地指定數組的類型。此代碼的工作原理：

class Person { 
    var firstName: String = "FirstName" 
    var lastName: String = "LastName" 

    init(inputFirstName: String, inputLastName: String) { 
     firstName = inputFirstName 
     lastName = inputLastName 
    } 
} 
var people: [Person] = [Person]() 

people.append(Person(inputFirstName: "A", inputLastName: "B")) 
people.append(Person(inputFirstName: "B", inputLastName: "C")) 
people.append(Person(inputFirstName: "C", inputLastName: "D")) 
people.append(Person(inputFirstName: "D", inputLastName: "E")) 
people.append(Person(inputFirstName: "E", inputLastName: "F")) 
people.append(Person(inputFirstName: "F", inputLastName: "G")) 
people.append(Person(inputFirstName: "G", inputLastName: "H")) 
people.append(Person(inputFirstName: "H", inputLastName: "I")) 

people.sort { $0.firstName > $1.firstName }