本文为原创文章，转载请标明出处

1. 通过CocoaPods安装SwiftyJSON

platform :ios, '10.0'

target '<Your Target Name>' do

  use_frameworks!

  pod 'SwiftyJSON', '~> 4.0.0'

end

2. 初始化

import SwiftyJSON

let json = JSON(data: dataFromNetworking)

let json = JSON(jsonObject)

if let dataFromString = jsonString.data(using: .utf8, allowLossyConversion: false) {

    let json = JSON(data: dataFromString)

}

3. 下标访问

// 方式1

let name = json[1]["list"][2]["name"].string

//方式2

let name = json[1,"list",2,"name"].string

//方式3

let keys:[JSONSubscriptType] = [1,"list",2,"name"]

let name = json[keys].string

let arrayNames =  json["users"].arrayValue.map({$0["name"].stringValue})

4. 循环遍历

不管JSON是数组类型还是字典类型key的类型都为String。

for (key,subJSON) in json {

    ...

}

5. 错误处理

枚举类型SwiftyJSONError包含unsupportedType、indexOutOfBounds、elementTooDeep、wrongType、notExist、invalidJSON、errorDomain。

6. 可选值获取

通过.number、.string、.bool、.int等方法获取到的是可选值。

if let id = json["user"]["name"].string {

    ...

} else {

    ...

    print(json["user"]["name"].error!)

}

7. 非可选值获取

通过.xxxValue方法获取到的是非可选值。

// 若不是String或为nil，返回“”

let name: String = json["name"].stringValue

8. 设置值

json["name"] = JSON("new-name")

json[0] = JSON(1)

json["name"].string =  "Jack"

json.arrayObject = [1,2,3,4]

json.dictionaryObject = ["name":"Jack", "age":25]

9. 原始数据

let rawObject: Any = json.object

let rawValue: Any = json.rawValue

do {

	let rawData = try json.rawData()

} catch {

	print("Error \(error)")

}

if let rawString = json.rawString() {

    ...

} else {

	print("json.rawString is nil")

}

10. 其他方法

exists

// 判断是否存在

if json["name"].exists()

merge

let original: JSON = [

    "first_name": "Theo",

    "age": 20,

    "skills": ["Coding", "Reading"],

    "address": [

        "street": "Software St",

        "zip": "210046",

    ]

]

let update: JSON = [

    "last_name": "Tsao",

    "age": 22,

    "skills": ["Writing"],

    "address": [

        "zip": "210012",

        "city": "Nanjing"

    ]

]

let updated = original.merge(with: update)

输出：

[

    "first_name": "Theo",

    "last_name": "Tsao",

    "age": 22,

    "skills": ["Coding", "Reading", "Writing"],

    "address": [

        "street": "Software St",

        "zip": "210012",

        "city": "Nanjing"

    ]

]

巴特西

iOS(Swift)学习笔记之SwiftyJSON的使用