gistfile1.cs

public static void Main(String[] args)
{
    var baseUrl = "http://exch2003/exchange/Alias/予定表";
    var xDoc = QueryToExchange(baseUrl,
                            String.Format(
                            @"SELECT
                                *
                              FROM
                                SCOPE('Shallow Traversal of """ + baseUrl + @"""')
                              WHERE
                                (""urn:schemas:calendar:dtstart"" >= CAST(""{0}"" as 'dateTime'))
                                AND
                                (""urn:schemas:calendar:dtstart"" <= CAST(""{1}"" as 'dateTime'))
                             ", DateTime.Today.ToString("o"), DateTime.Today.AddDays(1).AddSeconds(-1).ToString("o")));

    XNamespace xNsE = "urn:schemas:httpmail:";
    XNamespace xNsD = "DAV:";
    XNamespace xNsC = "urn:schemas:calendar:";
    var ret = from e in xDoc.Elements().Elements(xNsD + "response").Elements(xNsD + "propstat")
              where e.Element(xNsD + "status").Value == "HTTP/1.1 200 OK"
              let prop  = e.Element(xNsD + "prop")
              let start = DateTime.Parse(prop.Element(xNsC + "dtstart").Value)
              let end   = DateTime.Parse(prop.Element(xNsC + "dtend").Value)
              orderby start descending 
              select new
              {
                  Subject  = prop.Element(xNsE + "subject").Value,
                  Location = prop.Element(xNsC + "location").Value,
                  Start    = start,
                  End      = end,
                  Propstat = e
              };
}

private static XDocument QueryToExchange(String url, String query)
{
    XDocument requestXDoc = new XDocument(new XDeclaration("1.0", "UTF-8", "yes"),
                                          new XElement("{DAV:}searchrequest",
                                                       new XElement("{DAV:}sql", query)
                                              ));

    // データをWebDAVで取得
    using (WebClient webClient = new WebClient())
    {
        webClient.Headers["Accept"] = "text/xml, application/xml";
        webClient.Headers["Content-Type"] = "text/xml";
        webClient.UseDefaultCredentials = true;
        webClient.Encoding = Encoding.UTF8;
        return XDocument.Parse(webClient.UploadString(url, "SEARCH", requestXDoc.ToString()));
    }
}