获取当前登录windows的帐号

System.Security.Principal.WindowsPrincipal p = System.Threading.Thread.CurrentPrincipal as System.Security.Principal.WindowsPrincipal;
string strName1 = p.Identity.Name;
string strName2 = HttpContext.Current.User.Identity.Name.ToString();
string strName3 = Request.ServerVariables["AUTH_USER"]; //Finding with name
string strName4 = Request.ServerVariables[5]; //Finding with index

string domainName = System.Environment.UserDomainName;  //当前windows域IP
string userName = System.Environment.UserName.ToLower();   //当前登录帐号