来自JSON Api的Swift请求数据

Question

我试图创建一个从json api获得相应的函数，但函数返回的值比alamofire请求更快......有人可以帮助我吗？非常感谢你。代码如下。

func trainNameToTelecode(trainName: String) -> String {
    var returnTelecode: String = ""
    Alamofire.request("http://tra.ink/api/query/train?name=\(trainName)").responseJSON { (response) in
        let result = response.result
        guard let resultDict = result.value as? Dictionary<String,AnyObject> else {return}
        guard let bodyDict = resultDict["body"] as? [String:AnyObject] else {return}
        returnTelecode = bodyDict["telecode"] as! String
    }
    return returnTelecode
}

Answer 1

您可以使用完成处理程序，在您的请求完成时返回字符串，例如：

func trainNameToTelecode(trainName: String, completion: (String) -> Void) {
    Alamofire.request("http://tra.ink/api/query/train?name=\(trainName)").responseJSON { (response) in
        let result = response.result
        guard let resultDict = result.value as? Dictionary<String,AnyObject> else {return}
        guard let bodyDict = resultDict["body"] as? [String:AnyObject] else {return}

        if let returnTelecode = bodyDict["telecode"] as? String {
            completion(returnTelecode)
        } else {
            completion("telecode is nil")
        }
    }
}

//and where you call your function:
self.trainNameToTelecode(trainName: "yourName") { (telecode) in
    print(telecode)
}