Question

我相信下面的代码是用Swift 2编写的。如何将语法转换为最新的Swift（5）？

使用Xcode进行转换时，它会出现类似以下错误：

通话中额外的参数“ usingEncoding”

和

无法调用非函数类型“ URLSession”的值

原始（需要帮助转换）：

let request = NSMutableURLRequest(URL: NSURL(string: "http://www.sample.com/sample.php")!)
        request.HTTPMethod = "POST"

        let postString = "a=\(customerLabel!)"
        request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding)

        let task = NSURLSession.sharedSession().dataTaskWithRequest(request) {
            data, response, error in

            if error != nil {
                print("error=\(error)")
                return
            }

            print("response = \(response)")

            let responseString = NSString(data: data!, encoding: NSUTF8StringEncoding)
            print("responseString = \(responseString)")
        }
        task.resume()
    }

这是我的尝试，但有错误：

let request = NSMutableURLRequest(url: URL(string: "http://www.sample.com/sample.php")!)
request.httpMethod = "POST"
let postString = "a=\(customerLabel!)"
request.HTTPBody = postString.data(usingEncoding: NSUTF8StringEncoding)

let task = URLSession.sharedSession().dataTaskWithRequest(request) {
    data, response, error in

    if error != nil {
        print("error=\(error)")
        return
    }

    print("response = \(response)")

    let responseString = NSString(data: data!, encoding: NSUTF8StringEncoding)
    print("responseString = \(responseString)")
}
task.resume()

Answer 1

请勿使用NSMutableURLRequest。使用URLRequest。
不要使用NSString，请使用String。
查看URLSession文档，发现您需要shared，而不是sharedInstance()。
data(using .utf8)。
许多其他修复程序。

这是您的固定代码，可以在完成处理程序中更好地处理可选内容：

var request = URLRequest(url: URL(string: "http://www.sample.com/sample.php")!)
request.httpMethod = "POST"
let postString = "a=\(customerLabel!)"
request.httpBody = postString.data(using: .utf8)

let task = URLSession.shared.dataTask(with: request) { data, response, error in
    if let error = error {
        print("error=\(error)")
        return
    }

    print("response = \(response)")

    if let data = data, let responseString = String(data: data, encoding: .utf8) {
        print("responseString = \(responseString)")
    }
}
task.resume()

如何将以下代码从Swift 2转换为Swift 5？

1 个答案: