ios - 迁移到 Swift 2 时出错 : Invalid conversion from throwing function of type to non-throwing function type and use of undeclared type

Question

我正在尝试将 Swift 2 语法用于 try...do...catch 以进行错误处理，但在尝试修改我的代码后，我遇到了一些我无法弄清楚的错误。在此先感谢您的帮助。

在 dispatch_async 行，错误:从类型 '() throws -> ()' 到非抛出函数类型 'dispatch_block_t'(又名 '@convention(block) () -> () 的无效转换').

稍后在代码中，关于“let resultArray.NSArray”...我收到错误“使用未声明的类型 NSArray”。

func searchFlickrForString(searchStr:String, completion:(searchString:String!, FlickrPhotos:NSMutableArray!, error:NSError!)->()){
    let searchURL:String = FlickrHelper.URLForSearchString(searchStr)

    let queue:dispatch_queue_t = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)

    dispatch_async(queue, {

        var error:NSError?

        let searchResultString:String! = try String(contentsOfURL: NSURL(fileURLWithPath: searchURL), encoding: NSUTF8StringEncoding)
        do {
            // Parse JSON Response
            let jsonData:NSData! = searchResultString.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)

            let resultDict:NSDictionary! = try NSJSONSerialization.JSONObjectWithData(jsonData, options: []) as! NSDictionary
            do {
                let status:String = resultDict.objectForKey("stat") as! String
                if status ==  "fail" {
                    let error:NSError? = NSError(domain: "FlickrSearch", code: 0, userInfo: [NSLocalizedFailureReasonErrorKey:resultDict.objectForKey("message")!])

                    completion(searchString: searchStr, FlickrPhotos:  nil, error: error)
                } else {
                    let resultArray:NSArrray = resultDict.objectForKey("photos").objectForKey("photo") as NSArray

                    let flickrPhotos:NSMutableArray = NSMutableArray()

                    for photoObject in resultArray{
                        let photoDict:NSDictionary = photoObject as NSDictionary

                        var flickrPhoto:FlickrPhoto = FlickrPhoto()
                        flickrPhoto.farm = photoDict.objectForKey("farm") as Int
                        flickrPhoto.server = photoDict.objectForKey("farm") as String
                        flickrPhoto.secret = photoDict.objectForKey("farm") as String
                        flickrPhoto.photoID = photoDict.objectForKey("farm") as String

                        let searchURL:String = FlickrHelper.URLForFlickrPhoto(flickrPhoto, size: "m")
                        //download image
                        let imageData:NSData = NSData(contentsOfURL: searchURL, options: nil)

                    }
                }
            } catch let error as NSError{
                completion(searchString: searchStr, FlickrPhotos: nil, error: error)
            }
        } catch {
            //completion(searchString: searchStr, FlickrPhotos: nil, error: error)
        }


    })

}

Answer 1

要修复第一个错误，先移动第一个

do {

直属

dispatch_async(queue

对于您的第二个错误:将您的代码更改为

let resultArray = resultDict.objectForKey("photos")!.objectForKey("photo") as! NSArray

同时将每个“as”替换为“as!”

将 searchURL 声明更改为:

let searchURL = NSURL(string: FlickrHelper.URLForFlickrPhoto(flickrPhoto, size: "m"))