Swift 中 JSON 写入（NSConcreteMutableData）中的类型无效

Question

我调用 Rest API 以调用我有一些作为字典格式的参数并在某些时候传递给 api 我在转换子类型中崩溃

这里是我的示例代码：

    let configuration = NSURLSessionConfiguration .defaultSessionConfiguration()
    let session = NSURLSession(configuration: configuration)

    self.profieImage = UIImage(named: "calendar.png")

    let imageData = UIImageJPEGRepresentation(self.profieImage, 1)

    let params = ["fname":"Martin","lname":"Raj","gender":"Male","dob":"1997-9-14","email":"xx@gmail.com","mobileNumber":"00000","pancard":"vvvv","profileImg":imageData!] as Dictionary!

    let urlString = NSString(format:"http://my.api.call");
    print("url string is \(urlString)")
    let request : NSMutableURLRequest = NSMutableURLRequest()
    request.URL = NSURL(string: NSString(format: "%@", urlString)as String)
    request.HTTPMethod = "POST"
    request.timeoutInterval = 30
    request.addValue("mobile", forHTTPHeaderField: "true")
    request.addValue("token", forHTTPHeaderField: "")
    request.HTTPBody  = try! NSJSONSerialization.dataWithJSONObject(params, options: [])



    let dataTask = session.dataTaskWithRequest(request)
        {
            (let data: NSData?, let response: NSURLResponse?, let error: NSError?) -> Void in
            // 1: Check HTTP Response for successful GET request
            guard let httpResponse = response as? NSHTTPURLResponse, receivedData = data
                else {
                    print("error: not a valid http response")
                    return
            }

            switch (httpResponse.statusCode){
            case 200:
                let response = NSString (data: receivedData, encoding: NSUTF8StringEncoding)

                print("response==\(response)")

                default:
                break
            }    
    }

我的日志打印了这个语句：

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Invalid type in JSON write (NSConcreteMutableData)'

Answer 1

错误信息很清楚：

不支持 JSON 格式的NSData。

例如，您可以将数据转换为 Base-64 编码字符串

let imageDataBase64 = imageData!.base64EncodedStringWithOptions([])
let params = ["fname":"Martin","lname":"Raj","gender":"Male","dob":"1997-9-14","email":"xx@gmail.com","mobileNumber":"00000","pancard":"vvvv","profileImg":imageDataBase64]

在服务器端，您需要将字符串解码回NSData

params 是一个非可选字典（编译器可以推断），类型转换为隐式解包 Dictionary 是没有意义的，也不需要。