如何在 c# 中将 grant_type 设置为 key 并将 value 设置为 client_credentials (rest service)

Question

我有一个返回令牌的 API。使用邮递员，我可以通过在标题部分设置授权来获取令牌详细信息。根据 API 规范，我将单选按钮选择为 application/x-www-form-urlencoded，并在邮递员正文中将键值设置为 grant_type，并将值设置为 client_credentials。

当我尝试在 c# 中实现相同的目标时，我无法弄清楚如何将键值 grant_type 和值设置为 client_credentials。 下面是我的代码，当我运行代码时出现错误。任何人都可以帮助我在WebRequest 中将grant_type 设置为键和值client_credentials。我还附上了屏幕截图。

the underlying connection was closed an unexpected error occurred on send

以下是捕获的内部异常。 {"Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host."}

       var request = (HttpWebRequest)WebRequest.Create(url);
        request.Method = "POST";
        //request.ContentLength = 0;   // new commented

        ServicePointManager.Expect100Continue = true;
        ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls;
        string postData = "grant_type=client_credentials"; // Not sure if we can set the values like this
        ASCIIEncoding encoding = new ASCIIEncoding();
        byte[] bytes = encoding.GetBytes(postData);
        request.Headers.Add("Authorization", ConfigurationManager.AppSettings.Get("TokenAuthorizationKey").ToString());

        request.Timeout = 600000;
        request.ContentType = "application/x-www-form-urlencoded";
        request.ContentLength = bytes.Length;
        request.KeepAlive = true;
        Stream newStream = request.GetRequestStream();  // this Line throws Error
        newStream.Write(bytes, 0, bytes.Length);

        using (var response = (HttpWebResponse)request.GetResponse())
        {
            var responseValue = string.Empty;

            if (response.StatusCode != HttpStatusCode.OK)
            {
                var message = String.Format("Request failed. Received HTTP {0}", response.StatusCode);

                throw new ApplicationException(message);
            }

            using (var responseStream = response.GetResponseStream())
            {
                if (responseStream != null)
                    using (var reader = new StreamReader(responseStream))
                    {
                        responseValue = reader.ReadToEnd();
                    }
            }

            return responseValue;
        }  

Answer 1

您可以像下面这样更新您的代码，

var requestparams = new Dictionary<string, string>
                {
                    { "grant_type", "client_credentials" },
                };
 string postData = string.Join("&", requestparams.Select(kv => kv.Key + "=" + kv.Value).ToArray());

这样你就可以在你的正文中附加你的请求参数，这应该可以工作