Asp.Net核心-从后端进行API调用

Question

我有一个应用程序，它正在使用IHostedService从后端cs类调用API。使用基本的API调用("http://httpbin.org/ip")，它可以正常工作并返回正确的值，但是我现在需要调用一个Siemens API，它要求我设置一个Authorization，并在主体中放置"grant_type=client_credentials“。

 public async Task<string> GetResult()
    {
        string data = "";
        string baseUrl = "https://<space-name>.mindsphere.io/oauth/token";

        using (HttpClient client = new HttpClient())
        {
            client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", {ServiceCredentialID: ServiceCredentialSecret});

            using (HttpResponseMessage res = await client.GetAsync(baseUrl))
            {

                using (HttpContent content = res.Content)
                {

                    data = await content.ReadAsStringAsync();
                }
            }
        }

我想我已经正确地设置了头文件，但是直到完整的请求格式化后我才能确定。是否有可能将请求的正文设置为"grant_type=client_credentials"？

Answer 1

据我从西门子API文档可以看出，他们期望表单数据，所以它应该是这样的：

public async Task<string> GetResult()
{
    string data = "";
    string baseUrl = "https://<space-name>.mindsphere.io/oauth/token";

    using (HttpClient client = new HttpClient())
    {
        client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", {ServiceCredentialID: ServiceCredentialSecret});

        var formContent = new FormUrlEncodedContent(new[]
        {
            new KeyValuePair<string, string>("grant_type", "client_credentials")
        });

        using (HttpResponseMessage res = await client.PostAsync(baseUrl, formContent))
        {

            using (HttpContent content = res.Content)
            {    
                data = await content.ReadAsStringAsync();
            }
        }
    }
}