ios - NSURLSession dataTaskWithRequest Swift

Question

我有以下代码:

var resultData:NSData?

task = session!.dataTaskWithRequest(request) { (data: NSData!, response: NSURLResponse!, error: NSError!) in

    if ((error) != nil) {
        println("Error")
        return
    }
    resultData = data
}

task!.resume()

但是，执行后结果数据为nil。如何获取请求返回的数据？

Answer 1

检查你的数据是否为nil然后就可以使用了

这是一个 Swift 3 示例:

let url = NSURL(string: "https://itunes.apple.com/search?term=jack+johnson&limit=2")!
let request = NSMutableURLRequest(url: url as URL)
let session = URLSession.shared

let task = session.dataTask(with: request as URLRequest) { data, response, error in
    if error != nil {
        print("error: \(error!.localizedDescription): \(String(describing: error))")
    }
    else if data != nil {
        if let str = NSString(data: data!, encoding: String.Encoding.utf8.rawValue) {
            print("Received data:\n\(str)")
        }
        else {
            print("unable to convert data to text")
        }
    }

}
task.resume()