Swift2的數組

Question

我有兩個獨立的.swift文件。我想用ManagePerson.swift來管理我的Strings，比如添加和檢索。另一個ViewController.swift創建一個用於訪問數據的ManagePerson類數組。

在我ManagePerson.swift

func addPerson(name: String, code: String, description: String){ 
    self.name = name 
    self.code = code 
    self.description = description 
} 

在我ViewController.swift。

var personList = [PersonTable]() // Declared at class level 

for jsonObjectString in resultArray! { 
    let name = jsonObjectString["Name"] as! String 
    let code = jsonObjectString["Code"] as! String 
    let description = jsonObjectString["Description"] as! String 
    self.personList[count].addPerson(Name, code: code, description: description) 
    count++ 
} 

但是，我似乎無法執行.addPerson方法。我得到一個錯誤「主題：6：EXC_BAD_INSTRUCTION（代碼= EXC_I386_INVOP，子碼=爲0x0）」

Answer 1

首先任何情況下，假設你定義你的「人」類與（一）三個屬性;和（b）的init方法來設置這些屬性：

class Person { 
    let name: String 
    let code: String 
    let description: String 

    init(name: String, code: String, description: String) { 
     self.name = name 
     self.code = code 
     self.description = description 
    } 
} 

然後，實例化一個Person，它只是

let person = Person(name: "Joe Montana", code: "16", description: "Quarterback") 

如果你想這些Person對象的數組，你把它定義爲：

var personList = [Person]() 

因此也就與一個Person添加到該陣列中，它是：

personList.append(Person(name: "Joe Montana", code: "16", description: "Quarterback")) 

所以，如果resultArray是字典的一個數組，你添加項目，像這樣：

for dictionary in resultArray! { 
    let name = dictionary["Name"] as! String 
    let code = dictionary["Code"] as! String 
    let description = dictionary["Description"] as! String 
    personList.append(Person(name: name, code: code, description: description)) 
} 

但是，請注意，我們沒有惹count（因爲你可以添加到數組）。

或者，如果這些數值可能是nil，你定義這些爲選配：

class Person { 
    let name: String? 
    let code: String? 
    let description: String? 

    init(name: String?, code: String?, description: String?) { 
     self.name = name 
     self.code = code 
     self.description = description 
    } 
} 

和

for dictionary in resultArray! { 
    let name = dictionary["Name"] as? String 
    let code = dictionary["Code"] as? String 
    let description = dictionary["Description"] as? String 
    personList.append(Person(name: name, code: code, description: description)) 
} 

Answer 2

這是因爲self.personList[count]是nil它不包含的PersonTable