URLSession&JSONSerialization斯威夫特3
你读到这篇文章之前,请理解,我有点斯威夫特与一个初学者,我努力学习。我已经通过一些网站在得到答案的希望浏览,但我要么无法找到或做错误的。我一直在关注这个教程,但这是老不更新>>Tutorial I followed < <URLSession&JSONSerialization斯威夫特3
我也试图修改一些快速3 - 虽然我可能没有这样做。
我该如何正确地做URLSession?我得到这个错误:
invalid conversion from throwing function of type'(_, _, _) throws -> Void' to non-throwing function type
下面这一行:
let task : URLSessionDataTask = session.dataTask(with: request, completionHandler: {data, response, error -> Void in
和变量 “jsonDict” - 我得到的错误,我有事先
extra arg 'error' in call.
谢谢
var urlString:String = ("http://query.yahooapis.com/v1/public/yql?q=select * from yahoo.finance.quotes where symbol IN "+stringQuotes+"&format=json&env=http://datatables.org/alltables.env").addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)!
var url : URL = URL(string: urlString)!
var request: URLRequest = URLRequest(url:url)
let config = URLSessionConfiguration.default
let session = URLSession(configuration: config)
let task : URLSessionDataTask = session.dataTask(with: request, completionHandler: {data, response, error -> Void in
if((error) != nil) {
println(error.localizedDescription)
}
else {
var err: NSError?
var jsonDict = try JSONSerialization.JSONObject(with: data, options: JSONSerialization.ReadingOptions.mutableContainers, error: &err) as NSDictionary
if(err != nil) {
println("JSON Error \(err!.localizedDescription)")
}
else {
var quotes:NSArray = ((jsonDict.objectForKey("query") as NSDictionary).objectForKey("results") as NSDictionary).objectForKey("quote") as NSArray
DispatchQueue.main.async(execute: {
.default.post(name: Notification.Name(rawValue: kNotificationStocksUpdated), object: nil, userInfo: [kNotificationStocksUpdated:quotes])
})
}
}
})
task.resume()
}
请找到更新的代码为雨燕3.0
var urlString:String = ("http://query.yahooapis.com/v1/public/yql?q=select * from yahoo.finance.quotes where symbol IN "+stringQuotes+"&format=json&env=http://datatables.org/alltables.env").addingPercentEncoding(withAllowedCharacters: .urlFragmentAllowed)!
let url : URL = URL(string: urlString)!
let request: URLRequest = URLRequest(url:url)
let config = URLSessionConfiguration.default
let session = URLSession(configuration: config)
let task = session.dataTask(with: request) { (data, response, error) in
if(error != nil){
print(error?.localizedDescription ?? "")
}
else{
do{
let jsonDict:NSDictionary = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as! NSDictionary
let quotes:NSArray = ((jsonDict.object(forKey: "query") as! NSDictionary).object(forKey: "results") as! NSDictionary).object(forKey: "quote") as! NSArray
print(quotes)
}
catch{
print(error.localizedDescription)
}
}
};
task.resume()
注:我没有测试的代码。因为你没有指定URL参数
似乎是固定它,我想。谢谢!当你的意思是URL的参数...这样? '/http://query.yahooapis.com/v1/public/yql?q=select * from yahoo.finance.quotes where symbol IN(“AAPL”,“GOOG”,“FB”)&format = json&env = http: // datatables.org/alltables.env' – zya
是的,你是正确的我不知道你在传递什么'stringQuotes',现在你在评论中提到。谢谢 – Vinodh
一个更改我添加的url编码方法应该是'urlFragmentAllowed'而不是'urlHostAllowed',如果我使用'urlHostAllowed'无法达到雅虎api – Vinodh
你的问题是不是在URLSessionDataTask
但在您的completionHandler
。更具体地说在var jsonDict = try JSONSerialization...
位。 try
表示您的代码可能会抛出异常,但您不处理它(catch
)。这就是为什么编译器决定你的完成处理程序类型为(_, _, _) throws -> Void
,而dataTask
方法需要(_, _, _) -> Void
。
Here你可以找到信息如何使用try/catch
。
它应该是'var jsonDict = try JSONSerialization.JSONObject(with:data,options:JSONSerialization.ReadingOptions.mutableContainers)as NSDictionary',in swift 3 error argument removed – Vinodh
@Vinodh - 谢谢,我不认为这会很简单。 – zya
邮政它作为一个答案它会为别人 – Vinodh