如何使用 swift 解析 JSON 4
How to parse JSON using swift 4
我对获取水果的详细信息感到困惑
{
"fruits": [
{
"id": "1",
"image": "https://cdn1.medicalnewstoday.com/content/images/headlines/271/271157/bananas.jpg",
"name": "Banana"
},
{
"id": "2",
"image": "http://soappotions.com/wp-content/uploads/2017/10/orange.jpg",
"title": "Orange"
}
]
}
想要使用 "Decodable"
解析 JSON
struct Fruits: Decodable {
let Fruits: [fruit]
}
struct fruit: Decodable {
let id: Int?
let image: String?
let name: String?
}
let url = URL(string: "https://www.JSONData.com/fruits")
URLSession.shared.dataTask(with: url!) { (data, response, error) in
guard let data = data else { return }
do{
let fruits = try JSONDecoder().decode(Fruits.self, from: data)
print(Fruits)
}catch {
print("Parse Error")
}
你也可以给我推荐用于快速下载图像的 cocoapod 库
您遇到的问题是因为您的 JSON
为您的 Fruits 返回了不同的数据。
对于第一个 ID,它 returns 一个名为 name
的 String
,但在第二个 ID 中,它 returns 一个名为 title
的字符串。
此外,在解析 JSON 时,ID 似乎是 String
而不是 Int
。
因此您的数据有两个可选值。
因此,您的可解码结构应该如下所示:
struct Response: Decodable {
let fruits: [Fruits]
}
struct Fruits: Decodable {
let id: String
let image: String
let name: String?
let title: String?
}
因为你的 URL 似乎无效,我在我的主包中创建了 JSON 文件并且能够像这样正确解析它:
/// Parses The JSON
func parseJSON(){
if let path = Bundle.main.path(forResource: "fruits", ofType: "json") {
do {
let data = try Data(contentsOf: URL(fileURLWithPath: path), options: .mappedIfSafe)
let jsonResult = try JSONDecoder().decode(Response.self, from: data)
let fruitsArray = jsonResult.fruits
for fruit in fruitsArray{
print("""
ID = \(fruit.id)
Image = \(fruit.image)
""")
if let validName = fruit.name{
print("Name = \(validName)")
}
if let validTitle = fruit.title{
print("Title = \(validTitle)")
}
}
} catch {
print(error)
}
}
}
希望对您有所帮助...
模型样本:
public struct JsonData: Codable{
let data: [Data]?
let meta: MetaValue?
let linksData: LinksValue?
private enum CodingKeys: String, CodingKey{
case data
case meta
case linksData = "links"
}
}
enum BackendError: Error {
case urlError(reason: String)
case objectSerialization(reason: String)
}
struct APIServiceRequest {
static func serviceRequest<T>(reqURLString: String,
resultStruct: T.Type,
completionHandler:@escaping ((Any?, Error?) -> ())) where T : Decodable {
guard let url = URL(string: reqURLString) else {
print("Error: cannot create URL")
let error = BackendError.urlError(reason: "Could not construct URL")
completionHandler(nil, error)
return
}
let urlRequest = URLRequest(url: url)
let session = URLSession.shared
let task = session.dataTask(with: urlRequest) { (data, response, error) in
guard error == nil else {
completionHandler(nil, error)
return
}
guard let responseData = data else {
print("Error: did not receive data")
let error = BackendError.objectSerialization(reason: "No data in response")
completionHandler(nil, error)
return
}
let decoder = JSONDecoder()
do {
let books = try decoder.decode(resultStruct, from: responseData)
completionHandler(books, nil)
} catch {
print("error trying to convert data to JSON")
print(error)
completionHandler(nil, error)
}
}
task.resume()
}
}
要访问:
让 apiService = APIServiceRequest()
var dataArray:[字符串:任何]? //全局变量
apiService.serviceRequest(reqURLString: endPoint, resultStruct: VariantsModel.self, completionHandler: {dataArray,Error in})
POST 方法
func loginWS(endpoint: String, completionHandler: @escaping (Any?) -> Swift.Void) {
guard let sourceUrl = URL(string: endpoint) else { return }
let request = NSMutableURLRequest(url: sourceUrl)
let session = URLSession.shared
request.httpMethod = "POST"
request.addValue(vehiceHeader, forHTTPHeaderField: "X-Vehicle-Type")
request.addValue(contentHeader, forHTTPHeaderField: "Content-Type")
let task = session.dataTask(with: request as URLRequest) { data, response, error in
guard let data = data else { return }
do {
let responseData = try JSONDecoder().decode(JsonData.self, from: data)
print("response data:", responseData)
completionHandler(responseData)
} catch let err {
print("Err", err)
}
}.resume()
}
// Parse Json using decodable
// First in create Structure depends on json
//
//
//
struct Countory : Decodable {
let name: String
let capital: String
let region: String
}
let url = "https://restcountries.eu/rest/v2/all"
let urlObj = URL(string: url)!
URLSession.shared.dataTask(with: urlObj) {(data, responds, Error) in
do {
var countories = try JSONDecoder().decode([Countory].self, from: data!)
for country in countories {
print("Country",country.name)
print("###################")
print("Capital",country.capital)
}
} catch {
print(" not ")
}
}.resume()
我对获取水果的详细信息感到困惑
{
"fruits": [
{
"id": "1",
"image": "https://cdn1.medicalnewstoday.com/content/images/headlines/271/271157/bananas.jpg",
"name": "Banana"
},
{
"id": "2",
"image": "http://soappotions.com/wp-content/uploads/2017/10/orange.jpg",
"title": "Orange"
}
]
}
想要使用 "Decodable"
解析 JSONstruct Fruits: Decodable {
let Fruits: [fruit]
}
struct fruit: Decodable {
let id: Int?
let image: String?
let name: String?
}
let url = URL(string: "https://www.JSONData.com/fruits")
URLSession.shared.dataTask(with: url!) { (data, response, error) in
guard let data = data else { return }
do{
let fruits = try JSONDecoder().decode(Fruits.self, from: data)
print(Fruits)
}catch {
print("Parse Error")
}
你也可以给我推荐用于快速下载图像的 cocoapod 库
您遇到的问题是因为您的 JSON
为您的 Fruits 返回了不同的数据。
对于第一个 ID,它 returns 一个名为 name
的 String
,但在第二个 ID 中,它 returns 一个名为 title
的字符串。
此外,在解析 JSON 时,ID 似乎是 String
而不是 Int
。
因此您的数据有两个可选值。
因此,您的可解码结构应该如下所示:
struct Response: Decodable {
let fruits: [Fruits]
}
struct Fruits: Decodable {
let id: String
let image: String
let name: String?
let title: String?
}
因为你的 URL 似乎无效,我在我的主包中创建了 JSON 文件并且能够像这样正确解析它:
/// Parses The JSON
func parseJSON(){
if let path = Bundle.main.path(forResource: "fruits", ofType: "json") {
do {
let data = try Data(contentsOf: URL(fileURLWithPath: path), options: .mappedIfSafe)
let jsonResult = try JSONDecoder().decode(Response.self, from: data)
let fruitsArray = jsonResult.fruits
for fruit in fruitsArray{
print("""
ID = \(fruit.id)
Image = \(fruit.image)
""")
if let validName = fruit.name{
print("Name = \(validName)")
}
if let validTitle = fruit.title{
print("Title = \(validTitle)")
}
}
} catch {
print(error)
}
}
}
希望对您有所帮助...
模型样本:
public struct JsonData: Codable{
let data: [Data]?
let meta: MetaValue?
let linksData: LinksValue?
private enum CodingKeys: String, CodingKey{
case data
case meta
case linksData = "links"
}
}
enum BackendError: Error {
case urlError(reason: String)
case objectSerialization(reason: String)
}
struct APIServiceRequest {
static func serviceRequest<T>(reqURLString: String,
resultStruct: T.Type,
completionHandler:@escaping ((Any?, Error?) -> ())) where T : Decodable {
guard let url = URL(string: reqURLString) else {
print("Error: cannot create URL")
let error = BackendError.urlError(reason: "Could not construct URL")
completionHandler(nil, error)
return
}
let urlRequest = URLRequest(url: url)
let session = URLSession.shared
let task = session.dataTask(with: urlRequest) { (data, response, error) in
guard error == nil else {
completionHandler(nil, error)
return
}
guard let responseData = data else {
print("Error: did not receive data")
let error = BackendError.objectSerialization(reason: "No data in response")
completionHandler(nil, error)
return
}
let decoder = JSONDecoder()
do {
let books = try decoder.decode(resultStruct, from: responseData)
completionHandler(books, nil)
} catch {
print("error trying to convert data to JSON")
print(error)
completionHandler(nil, error)
}
}
task.resume()
}
}
要访问:
让 apiService = APIServiceRequest()
var dataArray:[字符串:任何]? //全局变量
apiService.serviceRequest(reqURLString: endPoint, resultStruct: VariantsModel.self, completionHandler: {dataArray,Error in})
POST 方法
func loginWS(endpoint: String, completionHandler: @escaping (Any?) -> Swift.Void) {
guard let sourceUrl = URL(string: endpoint) else { return }
let request = NSMutableURLRequest(url: sourceUrl)
let session = URLSession.shared
request.httpMethod = "POST"
request.addValue(vehiceHeader, forHTTPHeaderField: "X-Vehicle-Type")
request.addValue(contentHeader, forHTTPHeaderField: "Content-Type")
let task = session.dataTask(with: request as URLRequest) { data, response, error in
guard let data = data else { return }
do {
let responseData = try JSONDecoder().decode(JsonData.self, from: data)
print("response data:", responseData)
completionHandler(responseData)
} catch let err {
print("Err", err)
}
}.resume()
}
// Parse Json using decodable
// First in create Structure depends on json
//
//
//
struct Countory : Decodable {
let name: String
let capital: String
let region: String
}
let url = "https://restcountries.eu/rest/v2/all"
let urlObj = URL(string: url)!
URLSession.shared.dataTask(with: urlObj) {(data, responds, Error) in
do {
var countories = try JSONDecoder().decode([Countory].self, from: data!)
for country in countories {
print("Country",country.name)
print("###################")
print("Capital",country.capital)
}
} catch {
print(" not ")
}
}.resume()