我得到这个错误：
致命错误：在展开可选值时意外找到nil
2017-08-08 13:36:37.343479+0430 ostadcat[6976:1695644]致命错误：
在展开可选值时意外找到nil
我正在使用此功能连接到服务器：
func getFirstPageApplication(EMPTY:String,completionHandler: @escaping (_ response: AnyObject) -> ())
{
var strResponse = "null"
var request = URLRequest(url: URL(string: self.baseURL+"getFirstPageApplication")!)
request.httpMethod = "POST"
let postString = "EMAIL=\(EMPTY)"
request.httpBody = postString.data(using: .utf8)
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
if error != nil {
DispatchQueue.main.async {
completionHandler({} as AnyObject)
}
} else {
var mdata = String(data: data!, encoding: .utf8)
var mmdata = mdata?.data(using: String.Encoding.utf8, allowLossyConversion: false)!
if let usableData = mmdata {
do {
let jsonResult = try JSONSerialization.jsonObject(with: usableData, options:
JSONSerialization.ReadingOptions.mutableContainers)
//print("worked")
//print(jsonResult) //this part works fine
DispatchQueue.main.async {
completionHandler(jsonResult as AnyObject)
}
} catch {
DispatchQueue.main.async {
completionHandler({} as AnyObject)
}
print("JSON Processing Failed")
}
}
}
}
task.resume()
}
我的响应是一个JSON值，它的内容有UTF8字符集。
输出值与JSON不同，我得到了nil，因为我收到的JSON不是UTF8格式的。
如何使用UTF8实现此功能：
JSONSerialization.jsonObject？mdata的输出：Optional("{\"sliders\":[{\"id\":4,\"title\":\"\\u0647\\u0645\\u06cc\\u0634\\u0647 \\u0628\\u0647 \\u0622\\u0648\\u0627\\u0632 \\u0628\\u0627 \\u0627\\u0633\\u062a\\u0627\\u062f\\u06a9\\u062a\",\"image\":\"1500801181_ostadcat_slider_1.jpg\",\"status\":1,\"created_at\":\"2017-07-23 04:43:01\",\"updated_at\":\"2017-07-23 04:43:01\"},{\"id\":6,\"title\":\"\\u06cc\\u06a9\\u06cc \\u0628\\u0631\\u0627\\u06cc \\u0647\\u0645\\u0647, \\u0647\\u0645\\u0647 \\u0628\\u0631\\u0627\\u06cc \\u06cc\\u06a9\\u06cc\",\"image\":\"1500801699_ostadcat_slider_3.jpg\",\"status\":1,\"created_at\":\"2017-07-23 04:51:39\",\"updated_at\":\"2017-07-23 04:51:39\"},{\"id\":7,\"title\":\"\\u062d\\u0631\\u0641\\u0647 \\u0627\\u06cc \\u062a\\u0631\\u06cc\\u0646 \\u0627\\u067e\\u0644\\u06cc\\u06a9\\u06cc\\u0634\\u0646 \\u0645\\u0648\\u0633\\u06cc\\u0642\\u06cc\",\"image\":\"1500801728_ostadcat_slider_4.jpg\",\"status\":1,\"created_at\":\"2017-07-23 04:52:08\",\"updated_at\":\"2017-07-23 04:52:08\"},{\"id\":8,\"title\":\"\\u062a\\u0648 \\u0647\\u0645 \\u0645\\u06cc \\u062a\\u0648\\u0646\\u06cc \\u0645\\u062b\\u0644 \\u0645\\u0646 \\u0628\\u0627\\u0634\\u06cc!!!\",\"image\":\"1500801751_ostadcat_slider_2.jpg\",\"status\":1,\"created_at\":\"2017-07-23 04:52:31\",\"updated_at\":\"2017-07-23 04:52:31\"}],\"tutorials\":[{\"id\":1,\"home_image\":\"1500806287_img_home_test_6.png\",\"tutorial_image\":\"1500809220_Hot-Romanian-Inna-in-black-goggles-wallpapers.jpg\",\"tutorial_title\":\"\\u062e\\u0648\\u0627\\u0646\\u0646\\u062f\\u06af\\u06cc\",\"tutorial_description\":\"\\u0622\\u0645\\u0648\\u0632\\u0634 \\u062c\\u0627\\u0645\\u0639 \\u062e\\u0648\\u0627\\u0646\\u0646\\u062f\\u06af\\u06cc\",\"video\":\"1500810916_innaHot2.mp4\",\"video_title\":\"\\u062e\\u0648\\u0627\\u0646\\u0646\\u062f\\u06af\\u06cc \\u0631\\u0627 \\u062d\\u0631\\u0641\\u0647 \\u0627\\u06cc \\u06cc\\u0627\\u062f \\u0628\\u06af\\u06cc\\u0631\\u06cc\\u062f\",\"teacher_image\":\"1500808975_inna-dark-hair-white-dresses-digital-art.jpg\",\"teacher_name\":\"\\u0627\\u06cc\\u0646\\u0627\",\"teacher_bio\":\"\\u0628\\u0647\\u062a\\u0631\\u06cc\\u0646 \\u0627\\u0632 \\u0633\\u0627\\u0644 2009 \\u062a\\u0627 \\u0628\\u0647 \\u0627\\u0644\\u0627\\u0646\",\"status\":1,\"created_at\":\"2017-06-29 17:31:20\",\"updated_at\":\"2017-07-23 11:55:16\"},{\"id\":2,\"home_image\":\"1500802877_img_home_test_1.jpg\",\"tutorial_image\":\"1500802877_Image.png\",\"tutorial_title\":\"\\u0622\\u0645\\u0648\\u0632\\u0634 \\u06af\\u06cc\\u062a\\u0627\\u0631 \\u0627\\u0633\\u0644\\u0634\",\"tutorial_description\":\"\\u06af\\u06cc\\u062a\\u0627\\u0631 \\u0627\\u0633\\u0644\\u0634 \\u0631\\u0627 \\u06cc\\u0627\\u062f \\u0628\\u06af\\u06cc\\u0631\\u06cc\\u062f!!!\",\"video\":\"1500804433_oneRepublic.mp4\",\"video_title\":\"\\u0646\\u0645\\u0648\\u0646\\u0647 \\u0622\\u0645\\u0648\\u0632\\u0634 \\u06af\\u06cc\\u062a\\u0627\\u0631\",\"teacher_image\":\"1500802882_maxresdefault.jpg\",\"teacher_name\":\"\\u0648\\u0627\\u0646 \\u0631\\u06cc\\u067e\\u0627\\u0628\\u0644\\u06cc\\u06a9\",\"teacher_bio\":\"\\u06af\\u0631\\u0648\\u0647 \\u0648\\u0627\\u0646 \\u0631\\u06cc\\u067e\\u0627\\u0628\\u0644\\u06cc\\u06a9 \\u0634\\u0627\\u0645\\u0644 5 \\u0639\\u0636\\u0648\",\"status\":1,\"created_at\":\"2017-06-29 17:35:09\",\"updated_at\":\"2017-07-23 05:37:13\"}]}")
使用此功能后：
RestApiManager.sharedInstance.getFirstPageApplication(EMPTY:"-") {
response in
let sliders = JSON(response["sliders"])
print("response: \(response)")
}
我的响应与json格式不同：
response: {
sliders = (
{
"created_at" = "2017-07-23 04:43:01";
id = 4;
image = "1500801181_ostadcat_slider_1.jpg";
status = 1;
title = "\U0647\U0645\U06cc\U0634\U0647 \U0628\U0647 \U0622\U0648\U0627\U0632 \U0628\U0627 \U0627\U0633\U062a\U0627\U062f\U06a9\U062a";
"updated_at" = "2017-07-23 04:43:01";
},
{
"created_at" = "2017-07-23 04:51:39";
id = 6;
image = "1500801699_ostadcat_slider_3.jpg";
status = 1;
title = "\U06cc\U06a9\U06cc \U0628\U0631\U0627\U06cc \U0647\U0645\U0647, \U0647\U0645\U0647 \U0628\U0631\U0627\U06cc \U06cc\U06a9\U06cc";
"updated_at" = "2017-07-23 04:51:39";
},
{
"created_at" = "2017-07-23 04:52:08";
id = 7;
image = "1500801728_ostadcat_slider_4.jpg";
status = 1;
title = "\U062d\U0631\U0641\U0647 \U0627\U06cc \U062a\U0631\U06cc\U0646 \U0627\U067e\U0644\U06cc\U06a9\U06cc\U0634\U0646 \U0645\U0648\U0633\U06cc\U0642\U06cc";
"updated_at" = "2017-07-23 04:52:08";
},
{
"created_at" = "2017-07-23 04:52:31";
id = 8;
image = "1500801751_ostadcat_slider_2.jpg";
status = 1;
title = "\U062a\U0648 \U0647\U0645 \U0645\U06cc \U062a\U0648\U0646\U06cc \U0645\U062b\U0644 \U0645\U0646 \U0628\U0627\U0634\U06cc!!!";
"updated_at" = "2017-07-23 04:52:31";
}
);
tutorials = (
{
"created_at" = "2017-06-29 17:31:20";
"home_image" = "1500806287_img_home_test_6.png";
id = 1;
status = 1;
"teacher_bio" = "\U0628\U0647\U062a\U0631\U06cc\U0646 \U0627\U0632 \U0633\U0627\U0644 2009 \U062a\U0627 \U0628\U0647 \U0627\U0644\U0627\U0646";
"teacher_image" = "1500808975_inna-dark-hair-white-dresses-digital-art.jpg";
"teacher_name" = "\U0627\U06cc\U0646\U0627";
"tutorial_description" = "\U0622\U0645\U0648\U0632\U0634 \U062c\U0627\U0645\U0639 \U062e\U0648\U0627\U0646\U0646\U062f\U06af\U06cc";
"tutorial_image" = "1500809220_Hot-Romanian-Inna-in-black-goggles-wallpapers.jpg";
"tutorial_title" = "\U062e\U0648\U0627\U0646\U0646\U062f\U06af\U06cc";
"updated_at" = "2017-07-23 11:55:16";
video = "1500810916_innaHot2.mp4";
"video_title" = "\U062e\U0648\U0627\U0646\U0646\U062f\U06af\U06cc \U0631\U0627 \U062d\U0631\U0641\U0647 \U0627\U06cc \U06cc\U0627\U062f \U0628\U06af\U06cc\U0631\U06cc\U062f";
},
{
"created_at" = "2017-06-29 17:35:09";
"home_image" = "1500802877_img_home_test_1.jpg";
id = 2;
status = 1;
"teacher_bio" = "\U06af\U0631\U0648\U0647 \U0648\U0627\U0646 \U0631\U06cc\U067e\U0627\U0628\U0644\U06cc\U06a9 \U0634\U0627\U0645\U0644 5 \U0639\U0636\U0648";
"teacher_image" = "1500802882_maxresdefault.jpg";
"teacher_name" = "\U0648\U0627\U0646 \U0631\U06cc\U067e\U0627\U0628\U0644\U06cc\U06a9";
"tutorial_description" = "\U06af\U06cc\U062a\U0627\U0631 \U0627\U0633\U0644\U0634 \U0631\U0627 \U06cc\U0627\U062f \U0628\U06af\U06cc\U0631\U06cc\U062f!!!";
"tutorial_image" = "1500802877_Image.png";
"tutorial_title" = "\U0622\U0645\U0648\U0632\U0634 \U06af\U06cc\U062a\U0627\U0631 \U0627\U0633\U0644\U0634";
"updated_at" = "2017-07-23 05:37:13";
video = "1500804433_oneRepublic.mp4";
"video_title" = "\U0646\U0645\U0648\U0646\U0647 \U0622\U0645\U0648\U0632\U0634 \U06af\U06cc\U062a\U0627\U0631";
}
);
}
我这里有个例外：
func initialFirstView()
{
RestApiManager.sharedInstance.getFirstPageApplication(EMPTY:"-"){
response in
let sliders = JSON(response["sliders"])
print("response: \(response)")
for item in (sliders.array)! // the error is in this line
{
var slider = Slider.init(mid: String(describing: item["id"]), mtitle: String(describing: item["title"]), mimage: String(describing: item["image"]), mstatus: String(describing: item["status"]), mcreated_at: String(describing: item["created_at"]), mupdated_at: String(describing: item["updated_at"]))
self.sliders.append(slider)
}
self.showSliders()
}
}
我这里有个错误：
对于（滑块。数组）中的项！
此行的输出：
print("response: \(sliders)")是响应：未知
最佳答案
我得到了nil，因为我收到的JSON不是UTF8格式的。
不，你错了。JSONSerialization只能使用UTF-8编码的数据。并且JSONSerialization.jsonObject(with:options:)将有效的UTF-8编码的JSON数据转换为Swift（和Objective-C）可以处理的对象。
如何将UTF8用于此函数：JSONSerialization.jsonObject？
如上所述，JSONSerialization.jsonObject(with:options:)使用UTF-8。
我的响应与json格式不同：JSONSerialization.jsonObject(with:options:)将输入的JSON数据转换为Objective-C对象，如下所示：
JSON object -> NSDictionary
JSON array -> NSArray
JSON number -> NSNumber
JSON string -> NSString
JSON true -> NSNumber
JSON false -> NSNumber
JSON null -> NSNull
您看到的是
NSDictionary或NSArray的输出，JSONSerialization.jsonObject(with:options:)已成功完成转换。我这里有一个错误：对于（sliders.array）中的项！
此行的输出：
print("response: \(sliders)")是响应：未知
则前一行：
let sliders = JSON(response["sliders"])未按预期工作。可能是个JSON.init(_:)的错误。您没有指定要使用的库，但不需要使用此类库：
试试这个：
print("response: \(response)")
guard let response = response as? [String: Any] else {
fatalError("response is not a JSON object")
}
guard let sliders = response["sliders"] as? [[String: Any]] else {
fatalError("sliders is not a JSON array")
}
for item in sliders {
let slider = Slider(mid: String(item["id"] as? Int ?? 0),
mtitle: item["title"] as? String ?? "",
mimage: item["image"] as? String ?? "",
mstatus: String(item["status"] as? Int ?? 0),
mcreated_at: item["created_at"] as? String ?? "",
mupdated_at: item["updated_at"] as? String ?? "")
self.sliders.append(slider)
}
self.showSliders()
我不确定这是否会导致
JSON.init(_:)的意外行为，但在这行代码中：let jsonResult = try JSONSerialization.jsonObject(with: usableData, options:
JSONSerialization.ReadingOptions.mutableContainers)
您无需指定选项
JSONSerialization.ReadingOptions.mutableContainers。它可以简化为：let jsonResult = try JSONSerialization.jsonObject(with: usableData)