HttpWebRequest提交Form和上传文件的认证问题

最新推荐文章于 2022-06-27 17:11:27 发布

转载最新推荐文章于 2022-06-27 17:11:27 发布 · 3.7k 阅读

文章标签：

#credentials #sharepoint #server #windows #byte #.net

.NET 专栏收录该内容

67 篇文章

订阅专栏

本文介绍如何使用HttpWebRequest实现文件上传与表单提交，并解决了集成认证导致的Unauthorized错误问题。通过使用DefaultCredentials替代自定义NetworkCredential，确保了上传过程的成功。

HttpWebRequest提交Form和上传文件的认证问题

HttpWebRequest , 集成认证 , IIS , DefaultCredentials , Credentials

使用HttpWebRequest 调用在SharePoint 上开发的一个上传页面上传文件和提交Form数据，方法是：
1、先通过GET的方法获取Upload .aspx页的内容，用正则表达式过滤出所有的input元素，重要的如__VIEWSTATE等：

NetworkCredential credential = new NetworkCredential("userid", "password", "domain");
CookieContainer cookieContainer = new CookieContainer();
HttpWebRequest webRequest = HttpWebRequest.Create(url) as HttpWebRequest;
webRequest.Method = "GET";
webRequest.CookieContainer = cookieContainer;
HttpWebResponse webResponse = webRequest.GetResponse() as HttpWebResponse;
Stream responseStream = webResponse.GetResponseStream();
StreamReader streamReader = new StreamReader(responseStream, Encoding.UTF8);
string responseStr = streamReader.ReadToEnd();
……

复制代码

2、然后把Get取到的hidden域、需要输入的内容及文件内容编码POST到Web Server端，再读取Web Server的响应以判断是否上传成功：

byte[] aryPostData = Encoding.UTF8.GetBytes(strPostData);
FileStream fileStream = new FileStream(txtFile.Text, FileMode.Open, FileAccess.Read);
byte[] aryFileData = new byte[fileStream.Length];
fileStream.Read(aryFileData, 0, (int)fileStream.Length);
fileStream.Close();
byte[] aryBoundaryEnd = Encoding.UTF8.GetBytes("/r/n--" + boundary + "/r/n");
webRequest = HttpWebRequest.Create(url) as HttpWebRequest;
webRequest.CookieContainer = cookieContainer;
webRequest.Credentials = credential;
webRequest.Method = "OST";
webRequest.ContentType = "multipart/form-data; boundary=" + boundary;
webRequest.ContentLength = aryPostData.Length + aryFileData.Length + aryBoundaryEnd.Length;
webRequest.CookieContainer = cookieContainer;
webRequest.UserAgent = "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648; .NET CLR 3.5.21022)";
webRequest.Referer = referer;
responseStream = webRequest.GetRequestStream();
responseStream.Write(aryPostData, 0, aryPostData.Length);
responseStream.Write(aryFileData, 0, aryFileData.Length);
responseStream.Write(aryBoundaryEnd, 0, aryBoundaryEnd.Length);
responseStream.Flush();
responseStream.Close();
try
{
webResponse = webRequest.GetResponse() as HttpWebResponse;
responseStream = webResponse.GetResponseStream();
streamReader = new StreamReader(responseStream, Encoding.UTF8);
responseStr = streamReader.ReadToEnd();
}
catch (WebException exp)
{
if(exp.Response!=null)
System.Diagnostics.Trace.WriteLine(((HttpWebResponse)exp.Response).StatusDescription;
else
System.Diagnostics.Trace.WriteLine(exp.Message);
}

复制代码

客户端和Web Server处于同一个NT域中，由于该站点采用了Windows集成认证，所以new 了一个NetworkCredential作为认证凭证，提供了用户名、密码和域名信息：

NetworkCredential credential = new NetworkCredential("userid", "password", "domain");
...
webRequest.Credentials = credential;

复制代码

但是，虽然提供了正确的用户名和密码，每次在POST完Form数据后，从Web Server获取响应时：

webResponse = webRequest.GetResponse() as HttpWebResponse;

复制代码

总是报"Unauthorized"的错误，查看Web Server，文件已经成功传上去了，怪事。

后来把认证凭证改成了：

NetworkCredential credential = CredentialCache.DefaultCredentials as NetworkCredential;
...
webRequest.Credentials = credential;

复制代码

竟然不出错了，默认取当前登录到域的用户的帐户信息，正好与我当前的应用环境相附。

----------------------------------------------------------------------------------------------------------------------------
MSDN中对DefaultCredentials 的解释是：

CredentialCache.DefaultCredentials 属性
获取应用程序的系统凭据。
...
DefaultCredentials 属性仅适用于基于 NTLM、协商和 Kerberos 的身份验证。
DefaultCredentials 表示运行应用程序的当前安全上下文的系统凭据。对于客户端应用程序，这些通常是运行应用程序的用户的 Windows 凭据（用户名、密码和域）。对于 ASP.NET 应用程序，默认凭据是已登录的用户或正被模拟的用户的用户凭据。

ref: http://www.cnblogs.com/cowbird/archive/2005/03/04/113281.aspx