Alamofire 4.0 Router Type of expression is ambiguous without more context

Question

我正在转换为 Swift 3.0，并为 Alamofire 定制了 Router class。我的代码如下：

enum Router: URLRequestConvertible {

    case get(query: String, params: [String: AnyObject]?)
    case post(query: String, params: [String: AnyObject]?)
    case put(query: String, params: [String: AnyObject]?)
    case delete(query: String, params: [String: AnyObject]?)

    var urlRequest: NSMutableURLRequest {

        // Default to GET
        var httpMethod: HTTPMethod = .get

        let (path, parameters): (String, [String: AnyObject]?) = {
            switch self {
            case .get(let query, let params):
                // Set the request call
                httpMethod = .get
                // Return the query
                return (query, params)
            case .post(let query, let params):
                // Set the request call
                httpMethod = .post
                // Return the query
                return (query, params)
            case .put(let query, let params):
                // Set the request call
                httpMethod = .put
                // Return the query
                return (query, params)
            case .delete(let query, let params):
                // Set the request call
                httpMethod = .delete
                // Return the query
                return (query, params)
            }
        }()


        // Create the URL Request
        let urlRequest: NSMutableURLRequest
        if let url =  URL(string: Globals.BASE_URL + path) {
            urlRequest = NSMutableURLRequest(url: url)
        } else {
            urlRequest = NSMutableURLRequest()
        }

        // set header fields
        if let key = UserDefaults.standard.string(forKey: Globals.NS_KEY_SESSION) {
            urlRequest.setValue(key, forHTTPHeaderField: "X-XX-API")
        }

        // Add user agent
        if let userAgent = UserDefaults.standard.string(forKey: Globals.NS_KEY_USER_AGENT) {
            urlRequest.setValue(userAgent, forHTTPHeaderField: "User-Agent")
        }

        // Set the HTTP method
        urlRequest.httpMethod = httpMethod.rawValue

        // Set timeout interval to 20 seconds
        urlRequest.timeoutInterval = 20

        return Alamofire.URLEncoding().encode(urlRequest as! URLRequestConvertible, with: parameters)
    }

    func asURLRequest() throws -> URLRequest {
    }
}

这给我一个错误，说明 Type of expression is ambiguious without more context 在 Alamofire.URLEncoding()。这是什么意思？

在 https://github.com/Alamofire/Alamofire/blob/master/Documentation/Alamofire%204.0%20Migration%20Guide.md#parameter-encoding-protocol 的 Alamofire 文档中，他们有代码

public protocol ParameterEncoding {
    func encode(_ urlRequest: URLRequestConvertible, with parameters: Parameters?) throws -> URLRequest
}

Answer 1

这几乎是的重复检查一下，您将了解如何使用新的 ParameterEncoding，尤其是 URLRequestConvertible 现在是使用 func asURLRequest() throws -> URLRequest 而不是 var 实现的。

Alamofire 4.0 Router Type of expression is ambiguous without more context

Alamofire 4.0 Router Type of expression is ambiguous without more context

nsurlrequest

ios

swift

alamofire