HTTP Web request

创建Web请求

 method, ICredentials creds)
        {
            Uri u = new Uri(url);
            if ((Uri.UriSchemeHttp != u.Scheme) && (Uri.UriSchemeHttps != u.Scheme))
            {
                throw new ArgumentOutOfRangeException("url", url);
            }

            WebRequest wr = WebRequest.Create(u);
            HttpWebRequest http = wr as HttpWebRequest;

            http.AllowAutoRedirect = false;

            http.Method = method;
            http.Credentials = creds;
            http.PreAuthenticate = true;
            return http;
        }

判断URL是否存在或者有无权限访问:  "HEAD"

 url, ICredentials creds)
        {
            WebRequest wr = GetWebRequest(url, "HEAD", creds);
            wr.GetResponse();
        }

异常捕捉到 404: 代表页面不存在, 401: 无法认证

创建Folder: "MKCOL "

 url, ICredentials creds)
        {
            try
            {
                EnsureWebResourceExists(url, creds);
                return;
            }
            catch
            {
            }
            WebRequest wr = GetWebRequest(url, "MKCOL", creds);
            wr.GetResponse();
        }

上传文件: "PUT"

 localFile, ICredentials creds)
        {
            WebClient wc = new WebClient();
            wc.Credentials = creds;

            wc.UploadFile(url, "PUT", localFile);
        }

判断页面是否为一个Folder: "PROPFIND"

 url, ICredentials creds)
        {
            WebRequest wr = GetWebRequest(url, "PROPFIND", creds);
            wr.Headers.Add("Depth:0");
            wr.ContentLength = 0;
            WebResponse resp = wr.GetResponse();

            StreamReader sr = new StreamReader(resp.GetResponseStream());
            string s = sr.ReadToEnd();

            //this is a hack - should probably parse the XML, but this is good enough for now
            return s.Contains(@"<D:isFolder>t</D:isFolder>") || s.Contains("<a:iscollection b:dt=\"boolean\">1</a:iscollection>"); ;
        }