如何使用 HttpClient 发出 OPTIONS 请求

Posted 2023-03-30

【中文标题】如何使用 HttpClient 发出 OPTIONS 请求

【英文标题】：how to make an OPTIONS request with HttpClient

【发布时间】：2019-04-19 20:04:41

【问题描述】：

如何使用 System.Net.Http.HttpClient 发送 OPTIONS 请求

HttpClient 的公开方法

删除异步 GetAsync 后异步 PutAsync 其他人也很少.....

我期待一个 OptionsAsync

   switch (httpMethod) 
      case HTTP_METHODS.DELETE:
       
        httpResponseMessage = httpClient.DeleteAsync(uri).Result;
        break;
       
      case HTTP_METHODS.GET:
       
        httpResponseMessage = httpClient.GetAsync(uri).Result;
        break;
       
      case HTTP_METHODS.POST:
       
        httpResponseMessage = httpClient.PostAsync(uri, httpContent).Result;
        break;
       
      case HTTP_METHODS.PUT:
       
        httpResponseMessage = httpClient.PutAsync(uri, httpContent).Result;
        break;
       
      case HTTP_METHODS.OPTION:
       
        //not sure what method to call on httpclient here to make Options request
        httpResponseMessage = httpClient.PutAsync(uri, httpContent).Result;
        if (httpResponseMessage.Headers.Contains("X-CSRF-TOKEN")) 
         IEnumerable < string > headerValues = httpResponseMessage.Headers.GetValues("X-CSRF-TOKEN");
         csrfToken = headerValues.FirstOrDefault();
        
        break;
        
     

【问题讨论】：

你看过这个吗：***.com/questions/6660019/…

【参考方案1】：

这种方法没有包装器（例如OPTIONS 和HEAD），但您可以像这些包装器一样使用SendAsync：

var request = new HttpRequestMessage(HttpMethod.Options, "url");
var result = await _httpClient.SendAsync(request);

【参考方案2】：

为了获得预期的响应，您必须确保在请求中设置“Origin”标头，如下所示：

using var client = new HttpClient();
var message = new HttpRequestMessage(HttpMethod.Options, "url");
message.Headers.Add("Origin", "http://example.com");
var response = await client.SendAsync(message);