Question

我有以下webclient： -

using (WebClient wc = new WebClient())
   {

 var url = currentURL+ "home/scanserver";
 wc.Headers.Add("Authorization", token);
 var json =wc.UploadStringTaskAsync(url, "FQDN=allscan");
   }

现在我正在通过安全令牌＆amp;名为FQDN的数据。所以在接收器上Post动作方法我无法检索FQDN参数，

我尝试了以下但没有工作

string FQDN = Request.Form["FQDN"];

我也尝试在action方法参数中定义FQDN，如下所示： - public async Task<ActionResult> ScanServer(string FQDN)

Answer 1

如果FQDN是query parameter，请尝试

using (WebClient wc = new WebClient())
{
  var url = currentURL+ "home/scanserver?FQDN=allscan";
  wc.Headers.Add("Authorization", token);
  var json =wc.UploadStringTaskAsync(url, "");
}

修改

要以表单形式发布，请使用UploadValuesTaskAsync方法。

var url = currentURL+ "home/scanserver"; var args = new NameValueCollection { { "FQDN", "allscan" } }; var json = wc.UploadValuesTaskAsync(url, args);

json现在是Task<byte>而不是Task<string>，因此您必须将其转换为string;
之类的东西
var s = Encoding.Utf8.GetString(json.Result);

Answer 2

对于一个简单的查询参数，你可以像@Richard所说的那样做

using (WebClient wc = new WebClient())
{
    var url = currentURL+ "home/scanserver?FQDN=allscan";
    wc.Headers.Add("Authorization", token);
    var json =wc.UploadStringTaskAsync(url, "");
}

或者，如果您想发送长字符串或复杂对象MyObject，那么您可以这样做

using (WebClient wc = new WebClient())
{
    var url = currentURL+ "home/scanserver";
    wc.Headers.Add("Authorization", token);
    wc.Headers[HttpRequestHeader.ContentType] = "application/json";
    //here you can also pass a json serialized complex object
    var json =wc.UploadStringTaskAsync(url, "{FQDN:'allscan'}"); 
}

我在这里假设你的api方法看起来像

public void scanserver(string FQDN) //OR (MyClass myObject)
{
    //do something with token and FQDN 
    //OR use your complex object - myObject
}

Answer 3

UploadStringTaskAsync的返回值为Task<string>。您需要等待返回的任务，添加延续，或阻止线程等待返回结果。

阻止方法：

using (WebClient wc = new WebClient())
{
    var url = currentURL+ "home/scanserver";
    wc.Headers.Add("Authorization", token);
    var json = wc.UploadStringTaskAsync(url, "FQDN=allscan").Result;
}

使用await（必须在标记为async的方法内）：

string json;
using (WebClient wc = new WebClient())
{
    var url = currentURL + "home/scanserver";
    wc.Headers.Add("Authorization", token);
    json = await wc.UploadStringTaskAsync(url, "FQDN=allscan");
}

我如何从UploadStringTaskAsync调用中检索传递的数据

3 个答案: