我是使用
Swift语言进行iOS开发的初学者.我有一个JSON文件包含如下数据.
{
"success": true,"data": [
{
"type": 0,"name": "Money Extension","bal": "72 $","Name": "LK_Mor","code": "LK_Mor","class": "0","withdraw": "300 $","initval": "1000 $"
},{
},]
}
我想解析这个文件,并且必须返回包含JSON文件中数据的字典.这是我写的方法.
enum JSONError: String,ErrorType {
case NoData = "ERROR: no data"
case ConversionFailed = "ERROR: conversion from JSON Failed"
}
func jsonParserForDataUsage(urlForData:String)->NSDictionary{
var dicOfParsedData :NSDictionary!
print("json parser activated")
let urlPath = urlForData
let endpoint = NSURL(string: urlPath)
let request = NSMutableURLRequest(URL:endpoint!)
NSURLSession.sharedSession().dataTaskWithRequest(request) { (data,response,error) -> Void in
do {
guard let dat = data else {
throw JSONError.NoData
}
guard let dictionary: NSDictionary = try NSJSONSerialization.JSONObjectWithData(dat,options:.AllowFragments) as? NSDictionary else {
throw JSONError.ConversionFailed
}
print(dictionary)
dicOfParsedData = dictionary
} catch let error as JSONError {
print(error.rawValue)
} catch {
print(error)
}
}.resume()
return dicOfParsedData
}
您无法返回异步任务.你必须使用回调.
原文链接：https://www.f2er.com/swift/319614.html像这样添加一个回调：
completion: (dictionary: NSDictionary) -> Void
到您的解析器方法签名：
func jsonParserForDataUsage(urlForData: String,completion: (dictionary: NSDictionary) -> Void)
并调用您想要“返回”的数据可用的完成：
func jsonParserForDataUsage(urlForData: String,completion: (dictionary: NSDictionary) -> Void) {
print("json parser activated")
let urlPath = urlForData
guard let endpoint = NSURL(string: urlPath) else {
return
}
let request = NSMutableURLRequest(URL:endpoint)
NSURLSession.sharedSession().dataTaskWithRequest(request) { (data,error) -> Void in
do {
guard let dat = data else {
throw JSONError.NoData
}
guard let dictionary = try NSJSONSerialization.JSONObjectWithData(dat,options:.AllowFragments) as? NSDictionary else {
throw JSONError.ConversionFailed
}
completion(dictionary: dictionary)
} catch let error as JSONError {
print(error.rawValue)
} catch let error as NSError {
print(error.debugDescription)
}
}.resume()
}
jsonParserForDataUsage("http...") { (dictionary) in
print(dictionary)
}
