我如何使用WebRequest 证书属性发送基本认证头？ 为什么没有授权头与发送，即使 preAuthenticate 设置为true的要求？

 的WebRequest请求=（HttpWebRequest的）WebRequest.Create（https://api.github.com/user）;
request.Credentials =新的NetworkCredential（githubUsername，githubPassword）;
请求preAuthenticate = TRUE。
变种响应= request.GetResponse（）;
 

解决方案

服务器应该发送一个HTTP 401未授权响应code的包含的一个WWW身份验证的HTTP标头。

  WWW身份验证：基本境界=榜样
 

在preAuthenticate属性只适用的在的验证已经发生。从MSDN：

真正用后请求发送一个HTTP Authorization头   验证已经发生;否则为false。缺省值是   假的。

进行更深入的解释请参见其他的答案。

How can I use the Webrequest Credentials Property to send an basic authentication header? Why isn't the Authorization header send with the request even whenPreAuthenticate is set to true?

WebRequest request = (HttpWebRequest)WebRequest.Create("https://api.github.com/user");
request.Credentials = new NetworkCredential("githubUsername", "githubPassword");
request.PreAuthenticate = true;
var response = request.GetResponse();

The server should send a HTTP 401 Not Authorized response code containing a WWW-Authenticate HTTP header.

WWW-Authenticate: Basic realm="example"

The PreAuthenticate property only works after authentication has taken place. From MSDN:

true to send an HTTP Authorization header with requests after authentication has taken place; otherwise, false. The default is false.

See other answers for more in depth explanation.