我真的在努力把一个JSON文件读入Swift，这样我就可以玩它了。我花了2天的时间重新搜索和尝试不同的方法，但没有运气，所以我已经注册了StackOverFlow，看看是否有人能给我指点正确的方向.....
我的JSON文件叫做test。Json，并包含以下内容:
{
"person":[
{
"name": "Bob",
"age": "16",
"employed": "No"
},
{
"name": "Vinny",
"age": "56",
"employed": "Yes"
}
]
}
该文件直接存储在文档中，我使用以下代码访问它:
let file = "test.json"
let dirs : String[] = NSSearchPathForDirectoriesInDomains(
NSSearchpathDirectory.DocumentDirectory,
NSSearchPathDomainMask.AllDomainMask,
true) as String[]
if (dirs != nil) {
let directories: String[] = dirs
let dir = directories[0]
let path = dir.stringByAppendingPathComponent(file)
}
var jsonData = NSData(contentsOfFile:path, options: nil, error: nil)
println("jsonData \(jsonData)" // This prints what looks to be JSON encoded data.
var jsonDict = NSJSONSerialization.JSONObjectWithData(jsonData, options: nil, error: nil) as? NSDictionary
println("jsonDict \(jsonDict)") - This prints nil.....
如果有人能给我一个正确的方向，我可以反序列化JSON文件，并把它放在一个可访问的Swift对象，我会永远感激!
亲切的问候,
Krivvenz。
在清理和抛光我的代码之后，我来到了这两个函数，你可以添加到你的项目中，并使用它们非常整洁和快速地从json文件读取数据，并将数据转换为你想要的任何类型!
public func readDataRepresentationFromFile(resource: String, type: String) -> Data? {
let filePath = Bundle.main.path(forResource: resource, ofType: type)
if let path = filePath {
let result = FileManager.default.contents(atPath: path)
return result
}
return nil
}
然后在这个函数的帮助下，你可以将你的数据转换为任何你想要的类型:
public func getObject<T: Codable>(of type: T.Type, from file: String) -> T? {
guard let data = readDataRepresentationFromFile(resource: file, type: "json") else {
return nil
}
if let object = try? JSONDecoder().decode(type, from: data) {
return object
}
return nil
}
此代码的应用示例:
在你的代码中调用这个函数，给它你的json文件的名字，这就是你所需要的!
func getInputDataFromSomeJson(jsonFileName: String) -> YourReqiuredOutputType? {
return getObject(of: YourReqiuredOutputType.self, from: jsonFileName)
}
我使用下面的代码从FAQ-data中获取JSON。Json文件存在于项目目录中。
我在Xcode 7.3中使用Swift实现。
func fetchJSONContent() {
if let path = NSBundle.mainBundle().pathForResource("FAQ-data", ofType: "json") {
if let jsonData = NSData(contentsOfFile: path) {
do {
if let jsonResult: NSDictionary = try NSJSONSerialization.JSONObjectWithData(jsonData, options: NSJSONReadingOptions.MutableContainers) as? NSDictionary {
if let responseParameter : NSDictionary = jsonResult["responseParameter"] as? NSDictionary {
if let response : NSArray = responseParameter["FAQ"] as? NSArray {
responseFAQ = response
print("response FAQ : \(response)")
}
}
}
}
catch { print("Error while parsing: \(error)") }
}
}
}
override func viewWillAppear(animated: Bool) {
fetchFAQContent()
}
JSON文件结构:
{
"status": "00",
"msg": "FAQ List ",
"responseParameter": {
"FAQ": [
{
"question": “Question No.1 here”,
"answer": “Answer goes here”,
"id": 1
},
{
"question": “Question No.2 here”,
"answer": “Answer goes here”,
"id": 2
}
. . .
]
}
}
Swift 3.0, Xcode 8, iOS 10
if let path = Bundle.main.url(forResource: "person", withExtension: "json") {
do {
let jsonData = try Data(contentsOf: path, options: .mappedIfSafe)
do {
if let jsonResult = try JSONSerialization.jsonObject(with: jsonData, options: JSONSerialization.ReadingOptions(rawValue: 0)) as? NSDictionary {
if let personArray = jsonResult.value(forKey: "person") as? NSArray {
for (_, element) in personArray.enumerated() {
if let element = element as? NSDictionary {
let name = element.value(forKey: "name") as! String
let age = element.value(forKey: "age") as! String
let employed = element.value(forKey: "employed") as! String
print("Name: \(name), age: \(age), employed: \(employed)")
}
}
}
}
} catch let error as NSError {
print("Error: \(error)")
}
} catch let error as NSError {
print("Error: \(error)")
}
}
输出:
Name: Bob, age: 16, employed: No
Name: Vinny, age: 56, employed: Yes
