自定义 header 到 HttpClient 请求

Custom header to HttpClient request

如何将自定义 header 添加到 HttpClient 请求?我正在使用 PostAsJsonAsync 方法来 post JSON。我需要添加的自定义 header 是

"X-Version: 1"

这是我到目前为止所做的:

using (var client = new HttpClient()) {
    client.BaseAddress = new Uri("https://api.clickatell.com/");
    client.DefaultRequestHeaders.Accept.Clear();
    client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", "xxxxxxxxxxxxxxxxxxxx");
    client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
    var response = client.PostAsJsonAsync("rest/message", svm).Result;
}

我找到了问题的答案。

client.DefaultRequestHeaders.Add("X-Version","1");

应该向您的请求添加自定义 header

var request = new HttpRequestMessage {
    RequestUri = new Uri("[your request url string]"),
    Method = HttpMethod.Post,
    Headers = {
        { "X-Version", "1" } // HERE IS HOW TO ADD HEADERS,
        { HttpRequestHeader.Authorization.ToString(), "[your authorization token]" },
        { HttpRequestHeader.ContentType.ToString(), "multipart/mixed" },//use this content type if you want to send more than one content type
    },
    Content = new MultipartContent { // Just example of request sending multipart request
        new ObjectContent<[YOUR JSON OBJECT TYPE]>(
            new [YOUR JSON OBJECT TYPE INSTANCE](...){...}, 
            new JsonMediaTypeFormatter(), 
            "application/json"), // this will add 'Content-Type' header for the first part of request
        new ByteArrayContent([BINARY DATA]) {
            Headers = { // this will add headers for the second part of request
                { "Content-Type", "application/Executable" },
                { "Content-Disposition", "form-data; filename=\"test.pdf\"" },
            },
        },
    },
};

HttpRequestMessageclass里面有个Headers属性。您可以在那里添加自定义 headers,它将随每个 HTTP 请求一起发送。另一方面,HttpClient class 中的 DefaultRequestHeaders 设置 headers 与使用该客户端 object 发送的每个请求一起发送,因此名称为 默认请求Headers。

希望这能让事情变得更清楚,至少对于将来看到这个答案的人来说是这样。

这是一个基于 Anubis 的答案(这是一种更好的方法,因为它不会为每个请求修改 headers)但它更等同于原始问题中的代码:

using Newtonsoft.Json;
...

var client = new HttpClient();
var httpRequestMessage = new HttpRequestMessage
    {
        Method = HttpMethod.Post,
        RequestUri = new Uri("https://api.clickatell.com/rest/message"),
        Headers = { 
            { HttpRequestHeader.Authorization.ToString(), "Bearer xxxxxxxxxxxxxxxxxxx" },
            { HttpRequestHeader.Accept.ToString(), "application/json" },
            { "X-Version", "1" }
        },
        Content = new StringContent(JsonConvert.SerializeObject(svm))
    };

var response = client.SendAsync(httpRequestMessage).Result;

我在 HttpClient headers 中添加了 x-api-version,如下所示:

var client = new HttpClient(httpClientHandler)
{
    BaseAddress = new Uri(callingUrl)
};
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
client.DefaultRequestHeaders.Add("x-api-version", v2);

以防万一有人想知道如何调用 httpClient.GetStreamAsync() 没有重载需要 HttpRequestMessage 来提供自定义 headers 你可以使用@Anubis 给出的上述代码并调用

await response.Content.ReadAsStreamAsync()

如果您返回范围为 Header 的 blob url 作为 FileStreamResult

特别有用

我的两分钱。我同意 heug。接受的答案是令人费解的。让我们退一步。

默认 headers 适用于特定 HttpClient 发出的所有请求。因此,您将使用默认 headers 共享 headers.

_client.DefaultRequestHeaders.UserAgent.ParseAdd(_options.UserAgent);          

但是,我们有时需要 header 特定于某个请求。因此,我们会在方法中使用类似这样的东西:

public static async Task<HttpResponseMessage> GetWithHeadersAsync(this 
    HttpClient httpClient, string requestUri, Dictionary<string, string> headers)
    {
        using (var request = new HttpRequestMessage(HttpMethod.Get, requestUri))
        {
            foreach(var header in headers)
            {
                request.Headers.Add(header.Key, header.Value);
            }

            return await httpClient.SendAsync(request);
        }
    }

如果您只需要一个额外的 non-default header,您只需使用:

request.Headers.Add("X-Version","1")

更多帮助: How to add request headers when using HttpClient