     }
     
     public func urlSession(_ session: URLSession, dataTask: URLSessionDataTask, didReceive data: Data){
-        if let task = self[dataTask] {
+        if let task = self[dataTask] as? WTURLSessionDataTask {
             task.urlSession(session, dataTask: dataTask, didReceive: data)
         }else{
         }

        }
    }
    
    public func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?){
        self.error = error
        finish()
    }
    
    
    
    //URLSessionDownloadDelegate
    public func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didFinishDownloadingTo location: URL){
        
    }

    public func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didResumeAtOffset fileOffset: Int64, expectedTotalBytes: Int64){
        
    }
}
open class WTURLSessionUploadTask:WTURLSessionTask{

}

open class WTURLSessionManager:NSObject{
    
