C# LDAP认证登录

LDAP是轻量目录访问协议，英文全称是Lightweight Directory Access Protocol，一般都简称为LDAP。它是基于X.500标准的，但是简单多了并且可以根据需要定制。与X.500不同，LDAP支持TCP/IP，这对访问Internet是必须的。LDAP的核心规范在RFC中都有定义，所有与LDAP相关的RFC都可以在LDAPman RFC网页中找到。

bool checkResult = false;
                try
                {
                    string username = Request.Params.Get("username");
                    string userpwd = Request.Params.Get("userpwd");
                    string strLADPath = "LDAP://OU=事业部,DC=HOLD,DC=Company,DC=COM";
                   
                    DirectoryEntry objEntry = new DirectoryEntry(strLADPath);
                    objEntry.AuthenticationType = AuthenticationTypes.None;

                    DirectorySearcher deSearch = new DirectorySearcher(objEntry);
                    //过滤名称是否存在
                    deSearch.Filter = "(&(objectClass=user)(sAMAccountName=" + username + "))";
                    deSearch.SearchScope = SearchScope.Subtree;
                    //find the first instance 
                    SearchResult results = deSearch.FindOne();
                    //check username & userpwd
                    if (null != results)
                    {
                        DirectoryEntry objUserEntry = new DirectoryEntry(results.Path, username, userpwd);
                        if (null != objUserEntry && null != objUserEntry.Properties
                            && objUserEntry.Properties.Contains("cn"))
                        {
                            checkResult = true;
                        }
                    }

                    Response.Write("认证结果：" + checkResult.ToString());
                }
                catch (System.Exception ex)
                {
                    Response.Write("认证异常"+ex.StackTrace);
                    Response.Write("认证结果：" + checkResult.ToString());
                }