ios - 读取json文件并在 TableView 上显示错误:

Question

每次我在 API 上发布时，我都会将 Alamofire JSON 响应保存在文件中

{
{"response":99,"message":"You are signing in after Fri Jun 15 10:50:00 EDT 2018.","date":"2018-06-15T14:50:07.515+0000"}
{"response":99,"message":"You are signing in after Fri Jun 15 10:50:00 EDT 2018.","date":"2018-06-15T14:50:14.420+0000"}
{"response":99,"message":"You are signing in after Fri Jun 15 10:50:00 EDT 2018.","date":"2018-06-15T14:50:23.183+0000"}
}

然后我想在表格 View 中显示此响应，我试图反序列化，以便将其放入循环中，它给了我这个错误:

Error Domain=NSCocoaErrorDomain Code=3840 "Garbage at end." UserInfo={NSDebugDescription=Garbage at end.}

let DocumentDirURL = try! FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: true)

let fileURL = DocumentDirURL.appendingPathComponent("x").appendingPathExtension("json")
var readString = ""

do {
    readString = try String(contentsOf: fileURL)
    let data = readString.data(using: .utf8)!
    do {
        if let jsonArray = try JSONSerialization.jsonObject(with: data, options: []) as? [String:AnyObject] {
           let form_name = jsonArray[0]["message"] as? String
           print (" midas \(jsonArray) + ")
        } else {
            print("bad json")
        }
    } catch let error as NSError {
        print(error)
    }
}

编辑: 这是我从 Alamofire 灾中救出的东西:

.responseJSON() { response in

            if let data = response.data, let utf8Text = String(data: data, encoding: .utf8) {
               self.savestrin = utf8Text + "\n"
                print("Data: \(self.savestrin)")
            } 

            self.writeToFile(content: self.savestrin )

这是 writetofile 方法

func writeToFile(content: String) {
     let documentsPath = try! FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: true)

    let filePath = documentsPath.appendingPathComponent("x").appendingPathExtension("json")

    //Check if file exists
    if let fileHandle = FileHandle(forWritingAtPath: filePath.path) {
        //Append to file
        fileHandle.seekToEndOfFile()
        fileHandle.write(content.data(using: String.Encoding.utf8)!)
    }
    else {
        //Create new file
        do {
            try content.write(to: filePath, atomically: true, encoding: String.Encoding.utf8)
        } catch {
            print("Error creating \(filePath)")
        }
    }
}

更新:感谢 Dávid Pásztor 和 vadian，我设法解决了这个问题

let DocumentDirURL = try! FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: true)

    let fileURL = DocumentDirURL.appendingPathComponent("x").appendingPathExtension("json")


    do {

        var readString = try String(contentsOf: fileURL)
        let x = readString.components(separatedBy: "\n")
        print (" midas \(x)  ")

        for i in 1..<x.count{
            do{
            let y = x[i]
                print (" midas \(y)  ")

            let b = convertToDictionary(text: y)
                print (" midas1 \(b)  ")

                let date = try b?["date"]
                dictarr["date"] = "\(date)"
                 print (" midas \(dictarr["date"])  ")

现在的问题是我如何无法在 TableView 中填充它。我尝试过

dictdata.addObject(dictarr) but it gives me error

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)

        let datainrow = dictdata[indexPath.row]
//        cell.textLabel?.text = "\(datainrow.objectForKey("message")!)"
        // Configure the cell...

        return cell
    }

Answer 1

这是一个预期的错误，因为您的 JSON 文件无效。您需要将第一个外括号 {} 更改为方括号 []，因为您要存储字典数组，并且需要使用分隔各个响应逗号。

您的 JSON 应该是这样的:

[
{"response":99,"message":"You are signing in after Fri Jun 15 10:50:00 EDT 2018.","date":"2018-06-15T14:50:07.515+0000"},
{"response":99,"message":"You are signing in after Fri Jun 15 10:50:00 EDT 2018.","date":"2018-06-15T14:50:14.420+0000"},
{"response":99,"message":"You are signing in after Fri Jun 15 10:50:00 EDT 2018.","date":"2018-06-15T14:50:23.183+0000"}
]

你的 JSON 解析器逻辑也有缺陷。您不应该使用 let Reading = readString.components(separatedBy: ",") 将 JSON 分成组件，您应该简单地解析整个 JSON 文件。此外，无需将文件解析为 String，您可以直接将其读入 Data 并将其传递给 JSONSerialization。也不需要嵌套的 do-catch block ，并且 Swift 中 JSON 字典的类型应该是 [String:Any]，而不是 [String:AnyObject ] 字典数组是 [[String:Any]]。

do {
    let jsonData = try Data(contentsOf: fileURL)
    if let jsonArray = try JSONSerialization.jsonObject(with: jsonData) as? [[String:Any]] {
        let form_name = jsonArray.first?["message"] as? String
        print (" midas \(jsonArray) + ")
    } else {
        print("bad json")
    }
} catch {
    print(error)
}