json - 在 Swift 中解析 json 时出错

Question

我在尝试从 Google 博客解析某些 JSON 时遇到错误。

我收到的错误是

'Invalid conversion from throwing function of type '(_, _, _) throws -> Void' to non-throwing function type '(NSData?, NSURLResponse?, NSError?) -> Void'  

我用谷歌搜索了一下，我知道这与捕获错误有关，但我无法弄清楚它到底是什么，任何帮助将不胜感激:

import UIKit
import CoreData

class MasterViewController: UITableViewController {

var detailViewController: DetailViewController? = nil
override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    let url = NSURL(string: "https://www.googleapis.com/blogger/v3/blogs/10861780/posts?key=AIzaSyBwmI4AzMnBmr7oSVeL0EHdzMjXV1aATnQ")

    let session = NSURLSession.sharedSession()

    let task = session.dataTaskWithURL(url!, completionHandler: { (data, response, error) -> Void in
    if error != nil {
            print(error)
        } else {
           //print(NSString(data: data!, encoding: NSUTF8StringEncoding))

           do {

            let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.MutableContainers) as! NSDictionary
            if jsonResult.count > 0 {

                if let items = jsonResult["items"] as? NSArray {
                    for items in items {
                        print(items)

                    }

Answer 1

试试这个。我纠正了你的错误，只添加了一些大括号。

override func viewDidLoad() {
  super.viewDidLoad()

 let url = NSURL(string: "https://www.googleapis.com/blogger/v3/blogs/10861780/posts?key=AIzaSyBwmI4AzMnBmr7oSVeL0EHdzMjXV1aATnQ")

let session = NSURLSession.sharedSession()

let task = session.dataTaskWithURL(url!, completionHandler: { (data, response, error) -> Void in

  if error != nil {
    print(error)
  } else {
    //print(NSString(data: data!, encoding: NSUTF8StringEncoding))
    do {

      let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions(rawValue: 0)) as! NSDictionary
      if jsonResult.count > 0 {

        if let items = jsonResult["items"] as? NSArray {
          for items in items {
            print(items)

          }
        }
      }
    } catch let error as NSError {
      print(error)
    }
  }
})
  task.resume()

} // end braces of view did load