c# 用LDAP访问AD

//bteip：机器名
//bluetech：组织名
//域名：bluetech.com.cn
string strPath = "LDAP://bteip/OU=bluetech,DC=bluetech,DC=com,DC=cn";
DirectoryEntry de;
de = new DirectoryEntry(strPath,"administrator" ,"btmainsvr1234",AuthenticationTypes.None);
DirectorySearcher deSearch = new DirectorySearcher();
deSearch.SearchRoot =de;
//set the search filter
deSearch.Filter = "(&(objectClass=user)(sAMAccountName=willpower))";
deSearch.SearchScope = SearchScope.Subtree;
//find the first instance
SearchResult results= deSearch.FindOne();
de=new DirectoryEntry(results.Path,"administrator" ,"btmainsvr1234",AuthenticationTypes.None);
if(de.Properties.Contains("cn"))
MessageBox.Show(de.Properties["cn"][0].ToString()) ;