2016-08-24 93 views
1

有人能解釋一下這是什麼意思data?.name下面的代碼:這是什麼意思「的數據。名稱?」下面的代碼

公共靜態異步任務運行(HttpRequestMessage REQ,TraceWriter日誌)

{ 
    log.Info($"C# HTTP trigger function processed a request. RequestUri={req.RequestUri}"); 

    // parse query parameter 
    string name = req.GetQueryNameValuePairs() 
     .FirstOrDefault(q => string.Compare(q.Key, "name", true) == 0) 
     .Value; 

    // Get request body 
    dynamic data = await req.Content.ReadAsAsync<string>(); 

    // Set name to query string or body data 
    name = name ?? data?.name; 


    return name == null 
     ? req.CreateResponse(HttpStatusCode.BadRequest, "Please pass a name on the query string or in the request body") 
     : req.CreateResponse(HttpStatusCode.OK, "Hello " + name)); 
} 

在這個環節中:https://blog.xamarin.com/creating-a-serverless-backend-for-mobile-apps/

感謝

回答

3

這就是C#6 Null Conditional操作

如果數據爲空,它將防止data.name拋出異常,而返回null

+0

好極了!非常感謝。 – csharpUser