读取某变量的值

import Foundation

let headers = [
  "Connection": "keep-alive",
  "Cache-Control": "max-age=0",
  "Upgrade-Insecure-Requests": "1",
  "User-Agent": "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.81 Safari/537.36",
  "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8",
  "Accept-Encoding": "gzip, deflate, br",
  "Accept-Language": "zh-CN,zh;q=0.9",
  "cache-control": "no-cache",
]

let request = NSMutableURLRequest(url: NSURL(string: "http://127.0.0.1:39321/iotgateway/read?ids=Channel1.Device1.tag1,Channel1.Device1.tag2")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "GET"
request.allHTTPHeaderFields = headers

let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
  if (error != nil) {
    print(error)
  } else {
    let httpResponse = response as? HTTPURLResponse
    print(httpResponse)
  }
})

dataTask.resume()