JSON解析迅速，数组在NSURLSession之外没有任何值

这个想法是使用“回调”。

在这里，我为您想要获得的NSArray做了一个：

completion: (dataArray: NSArray)->()


我们创建一个获取数组的函数，并将此回调添加到函数的签名中：

func getDataArray(urlString: String, completion: (dataArray: NSArray)->())


数组准备就绪后，我们将使用回调：

completion(dataArray: theNSArray)


完整功能如下所示：

func getDataArray(urlString: String, completion: (dataArray: NSArray)->()) {
if let url = NSURL(string: urlString) {
NSURLSession.sharedSession().dataTaskWithURL(url) {(data, response, error) in
if error == nil {
if let data = data,
json1 = NSString(data: data, encoding: NSUTF8StringEncoding),
data1 = json1.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false) {
do {
let json = try NSJSONSerialization.JSONObjectWithData(data1, options: [])
if let jsOnArray= json as? NSArray {
completion(dataArray: jsonArray)
}
} catch let error as NSError {
print(error.localizedDescription)
}
} else {
print("Error: no data")
}
} else {
print(error!.localizedDescription)
}
}.resume()
}
}


现在我们像这样使用此函数，不再有异步问题：

getDataArray("http://192.1.2.3/PhpProject1/getFullJson.php") { (dataArray) in
for dataDictionary in dataArray {
if let notId = dataDictionary["ID"] as? String {
self.IdDEc.append(notId)
}
}
print("id out count = ", self.IdDEc.count)
}


更新+修复和改进。

func getcontent(from url: String, completion: @escaping ([[String: Any]])->()) {
if let url = URL(string: url) {
URLSession.shared.dataTask(with: url) { (data, response, error) in
if error == nil {
if let data = data {
do {
let json = try JSONSerialization.jsonObject(with: data, options: [])
if let cOntent= json as? [[String: Any]] { // array of dictionaries
completion(content)
}
} catch {
// error while decoding JSON
print(error.localizedDescription)
}
} else {
print("Error: no data")
}
} else {
// network-related error
print(error!.localizedDescription)
}
}.resume()
}
}
getcontent(from: "http://192.1.2.3/PhpProject1/getFullJson.php") { (result) in
// 'result' is what was given to 'completion', an array of dictionaries
for dataDictionary in result {
if let notId = dataDictionary["ID"] as? String {
// ...
}
}
}