iOS Swift 3为同步和异步请求创建URLSession扩展

iOS Swift 3 create URLSession extension for synchronous and asynchronous request

我将在Swift 3中为URLSession创建扩展以创建同步和异步请求。这是我的实现

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extension URLSession {
func sendSynchronousRequest(request: URL, completionHandler: @escaping (Data?, URLResponse?, Error?) -> Void) {
let semaphore = DispatchSemaphore(value: 0)

let task = self.dataTask(with: request) { (data, response, error) in
completionHandler(data,response,error)
semaphore.signal()
}
task.resume()
semaphore.wait(timeout: .distantFuture)
}

func sendAsynchronousRequest(request: URLRequest, completionHandler: @escaping (Data?, URLResponse?, Error?) -> Void) -> URLSessionDataTask {
let task = self.dataTask(with: request) { data, response, error in
completionHandler(data, response, error)
}
task.resume()
return task
}
}

我有Xcode建议我将@escaping插入到函数中。我不知道实施是否正确

我在这一行也有警告：

enter image description here

有人知道如何更正扩展名吗？

我找到了这个实现，但是在swift1 / 2中不记得了。这不是我自己的。但是我很快改写了它。我只是不记得我在哪里找到的：/

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func synchronousDataTaskWithURL(url: URL) -> (Data?, URLResponse?, Error?) {
var data: Data?, response: URLResponse?, error: Error?

let semaphore = DispatchSemaphore(value: 0)

dataTask(with: url) {
data = $0; response = $1; error = $2
semaphore.signal()
}.resume()

semaphore.wait()

return (data, response, error)
}