Alamofire 响应处理程序的问题

Posted 2023-02-24

【中文标题】Alamofire 响应处理程序的问题

【英文标题】：Problems with Alamofire response handler

【发布时间】：2021-07-23 17:38:12

【问题描述】：

对于我的项目，我想解析一个 Alamofire JSON 响应并将其保存在 Realm 中。我已经通过从 Mock-API 获取 JSON 进行了测试，它运行良好，但是当我尝试将我的代码合并到我的 AM 响应处理中时，我收到了这个错误：

从 '(AFDataResponse) throws -> Void' 类型的抛出函数（又名 '(DataResponse) throws -> ()'）到非抛出函数类型 '(AFDataResponse) -> Void 的无效转换' (aka '(DataResponse) -> ()')

响应代码如下所示：

 .responseJSON  response in //this is where I'm getting the error
                print(response)
        self.books = [Books]()
    do 
        if let json = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as! [String: AnyObject] 
        
        if let booksFromJson = json["books"] as? [[String : AnyObject]]
            for bookFromJson in booksFromJson 
                let book = Books()
                if let title = bookFromJson["title"] as? String, let author = bookFromJson["author"] as? String, let imageLink = bookFromJson["imageLink"] as? String 
                    
                    book.author = author
                    book.title = title
                    book.imageLink = imageLink
                    
                
                self.books?.append(book)
   
                                 

这是我的 AM-Request 整体：

public func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) 
 if let image:UIImage = info[UIImagePickerController.InfoKey.editedImage] as? UIImage 
     self.myImage = image
     
     
     AF.upload(multipartFormData:  (multipartFormData) in
        multipartFormData.append(self.myImage.jpegData(compressionQuality: 0.5)!, withName: "image", fileName: "image.png", mimeType: "image/jpeg")
     
     , to: "https://booknerdvirtualreadinglist.herokuapp.com/getbook" , headers: nil )
     .uploadProgress  progress in
                 print(progress)
             
     .responseJSON  response in
                print(response)
        self.books = [Books]()
    do 
        if let json = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as! [String: AnyObject] 
        
        if let booksFromJson = json["books"] as? [[String : AnyObject]]
            for bookFromJson in booksFromJson 
                let book = Books()
                if let title = bookFromJson["title"] as? String, let author = bookFromJson["author"] as? String, let imageLink = bookFromJson["imageLink"] as? String 
                    
                    book.author = author
                    book.title = title
                    book.imageLink = imageLink
                    
                
                self.books?.append(book)
   
                                 
dismiss(animated: true, completion: nil)
                                

提前谢谢你！

【问题讨论】：

为什么要复制？另外，如果我没记错的话，应该是：switch response case .failure(let afError): print(error); case .success(let res): if let json = res as? [String: AnyObject] //do the rest as your code

不相关但 JSON 值绝不是引用类型 (AnyObject)，它是 Any。而.mutableContainers 在 Swift 中毫无意义，特别是如果您将结果分配给 im 可变常量。

请将您的解决方案发布在答案中，而不是问题中。谢谢。

【参考方案1】：

您没有正确捕获错误，因为您的“try catch”只有一个 do 块。

这是在 Swift 中正确处理错误的方法：

do 
    // some throwing code
 catch 
    print("Failed with error \(error)")

缺少关键部分。