小编Pri*_*ess的帖子

我是xcode编程的新手,我正在尝试在Swift 2中实现一个发出HTTP Get请求的App.升级xcode 7后显示错误:

Cannot convert value of type 
'(NSData!, response: NSURLResponse!, err: NSError!) -> ()'
to expected argument type 
'(NSData?, NSURLResponse?, NSError?) -> Void'

(此代码段使用swift 1.2的旧错误处理.)任何人都可以帮助我,请问如何在Swift 2.0中实现它.

    request.HTTPMethod = "GET"
    let session = NSURLSession.sharedSession()
    let task = session.dataTaskWithRequest(request, completionHandler:loadedData)

    task.resume()


}

func loadedData(data:NSData!, response:NSURLResponse!, err:NSError!){

    if(err != nil)
    {
        print(err?.description)
    }
    else
    {
        var jsonResult: NSDictionary = NSDictionary()
        let httpResponse = response as! NSHTTPURLResponse
        print("\(httpResponse.statusCode)")

        if (httpResponse.statusCode == 200)
        {

            jsonResult = (try! NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers)) as! NSDictionary
            print(jsonResult) …