我正在尝试将JSON格式的数据从服务器加载到IOS应用程序中。
这是我的JSON:
[
{
"BankName": "bank1",
"CurrencyName": "cur1",
"SellRate": "0.65",
"BuyRate": "0.55",
"OfficialRate": "0.6"
},
{
"BankName": "bank1",
"CurrencyName": "cur2",
"SellRate": "1.65",
"BuyRate": "1.55",
"OfficialRate": "1.6"
}
]
我的项目中有两个文件:
一:
import Foundation
class Shot {
var bankName: String!
var currencyName: String!
var sellRate: String!
var buyRate: String!
var offRate: String!
init (data: NSDictionary) {
self.bankName = getStringFromJSON(data, key:"BankName")
self.currencyName = getStringFromJSON(data, key:"CurrencyName")
self.sellRate = getStringFromJSON(data, key:"SellRate")
self.buyRate = getStringFromJSON(data, key:"BuyRate")
self.offRate = getStringFromJSON(data, key: "OfficialRate")
}
func getStringFromJSON(data: NSDictionary, key: String) -> String {
if let info = data[key] as? String{
return info
}
return ""
}
}
二:
import Foundation
class JsonTest {
func loadJson(completion: ((AnyObject) -> Void)!) {
var urlString = "http://a.com/g.php"
let session = NSURLSession.sharedSession()
let sourceUrl = NSURL(string: urlString)
var task = session.dataTaskWithURL(sourceUrl!){
(data, response, error) -> Void in
if error != nil {
println(error.localizedDescription)
} else {
var error: NSError?
var jsonData = NSJSONSerialization.JSONObjectWithData(data, options: .MutableContainers, error: &error) as NSArray
var shots = [Shot]()
println(jsonData)
for shot in jsonData{
let shot = Shot(data: shot as NSDictionary)
shots.append(shot)
}
println(shots) //[jsontest.Shot, jsontest.Shot]
}
}
task.resume()
}
}
我正在尝试在应用程序启动时自动填充数组。为此,我在mainViewController类中有一个代码。
override func viewDidLoad() {
super.viewDidLoad()
let api = JsonTest()
api.loadJson(nil)
}
当我试图在第二个文件中打印shots变量时,就会出现这个问题。
当我期待字典数组时,它返回
[jsontest.Shot, jsontest.Shot]
。println(jsonData)
工作正常,显示来自URL的JSON数据。有人能告诉我我的程序出了什么问题吗?
最佳答案
“shots”是Shot的实例数组,而不是字典:
class Shot {
var bankName: String!
var currencyName: String!
var sellRate: String!
var buyRate: String!
var offRate: String!
init (data: NSDictionary) {
self.bankName = getStringFromJSON(data, key:"BankName")
self.currencyName = getStringFromJSON(data, key:"CurrencyName")
self.sellRate = getStringFromJSON(data, key:"SellRate")
self.buyRate = getStringFromJSON(data, key:"BuyRate")
self.offRate = getStringFromJSON(data, key: "OfficialRate")
}
func getStringFromJSON(data: NSDictionary, key: String) -> String {
if let info = data[key] as? String{
return info
}
return ""
}
}
var shots = [Shot]()
let urlString = "http://almazini.lt/getrates.php"
let sourceUrl = NSURL(string: urlString)
// Using NSData instead of NSURLSession for experimenting in Playground
let data = NSData(contentsOfURL: sourceUrl!)
var error: NSError?
// As I'm using Swift 1.2 I had to change "as" with "as!"
let jsonData = NSJSONSerialization.JSONObjectWithData(data!, options: .MutableContainers, error: &error) as! NSArray
for shot in jsonData{
let shot = Shot(data: shot as! NSDictionary)
shots.append(shot)
}
println(shots[0].bankName)
Swift 2的更新
var shots = [Shot]()
let urlString = "http://almazini.lt/getrates.php"
// Using NSData instead of NSURLSession for experimenting in Playground
if let sourceUrl = NSURL(string: urlString) {
NSURLSession.sharedSession().dataTaskWithURL(sourceUrl, completionHandler: { (data, response, error) in
if error == nil {
if let data = data, jsonData = try? NSJSONSerialization.JSONObjectWithData(data, options: []), jsonArray = jsonData as? [NSDictionary] {
for item in jsonArray {
let shot = Shot(data: item)
shots.append(shot)
}
print(shots[0].bankName)
} else {
print("no JSON data")
}
} else {
print(error!.localizedDescription)
}
}).resume()
}